:Battle of Saipan

File:Map of B-29 range from Saipan.svg be within the {{convert|1600|mi|km|abbr=on}} range of the B-29 bomber|alt=map of the western Pacific. An orange line marking the Japanese defenses runs from the Kuriles to New Guinea and Java. There is an arc showing the range of B-29 bombers that overlaps with Japan and the Philippines]]

Up to early 1944, Allied operations against the Japanese military in the Pacific were focused on securing the lines of communication between Australia and the United States. These operations had recaptured the Solomon Islands, eastern New Guinea, western New Britain, the Admiralty Islands, and the Gilbert and Marshall Islands.{{sfn|Smith|1996|p=[https://archive.org/details/TheApproachToThePhilippines-nsia/page/n17 1]}}

To defeat Japan, Admiral Ernest J. King, Commander in Chief, United States Fleet, sought to execute War Plan Orange,{{sfnm|Hopkins|2008|1p=[https://archive.org/details/pacificwarstrate0000hopk/page/146 146]|Miller|1991|2pp=[https://archive.org/details/warplanorangeuss0000mill/page/336 336–337]|Symonds|2022|3pp=[{{Google Books|id=hKJnEAAAQBAJ|pg=PA229|plainurl=yes}} 229]–[{{Google Books|id=hKJnEAAAQBAJ|pg=PA230|plainurl=yes}} 230]|Toll|2015|4p=[https://archive.org/details/conqueringtidewa0000toll/page/306 306]}} which the Naval War College had been developing for four decades in the event of a war.{{sfnm|1a1=Hopkins|1y=2008|1p=[https://archive.org/details/pacificwarstrate0000hopk/page/5 5]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2pp= [https://archive.org/details/historyofusmarin03usma/page/3 3–4]|3a1=Vlahos|3y=1980|3p=[https://archive.org/details/blueswordnavalwa00vlah/page/118 118]}} The plan envisioned an offensive through the Central Pacific that originated from Hawaii, island-hopped through Micronesia and the Philippines, forced a decisive battle with the Japanese Navy, and brought about an economic collapse of Japan.{{sfnm|Miller|1991|1pp=[https://archive.org/details/warplanorangeuss0000mill/page/4 4–5]|Toll|2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/306 306]}}

As early as the Casablanca Conference in January 1943, King presented the case to the Combined Chiefs of Staff for an amphibious offensive in the Central Pacific – including the Marshall Islands and Truk – that would capture the Mariana Islands. He stated that the occupation of the Marianas – specifically Saipan, Tinian and Guam – would cut the sea and air route from the Japanese home islands to the western Pacific,{{sfnm|1a1=Heinrichs|1a2=Gallicchio|1y=2017|1p=[https://archive.org/details/implacablefoeswa0000hein/page/92 92]|2a1=Morison|2y=1981|2pp=[https://archive.org/details/newguineamariana0008samu/page/5 5–6]|2ps=: see {{harvnb|Casablanca Conference|1943|pp=185–186}} for King's argument.}} but the Combined Chiefs of Staff made no commitment at the time.{{sfn|Y'Blood|1981|p=[https://archive.org/details/redsunsettingbat0000yblo_f0a9/page/4 4]}} General Douglas MacArthur, Supreme Commander of Allied Forces in the Southwest Pacific Area, objected to King's proposed Central Pacific offensive.{{sfnm|1a1=Shaw|1a2=Nalty|1a3=Turnbladh|1y=1989|1p= [https://archive.org/details/historyofusmarin03usma/page/235 235]|2a1=Y'Blood|2y=1981|2pp=[https://archive.org/details/redsunsettingbat0000yblo_f0a9/page/4 4–5]}} He argued that it would be costly and time-consuming and would pull resources away from his drive in the Southwest Pacific toward the Philippines.{{sfnm|Hopkins|2008|1p=[https://archive.org/details/pacificwarstrate0000hopk/page/174 174–175]|Smith|1996|2pp=[https://archive.org/details/TheApproachToThePhilippines-nsia/page/n19 3–4]|Symonds|2022|3p=[{{Google Books|id=hKJnEAAAQBAJ|pg=PA232|plainurl=yes}} 232]}}

At the Quebec Conference in August 1943, King continued to advocate for including the Marianas in a Central Pacific offensive.{{harvnb|Y'Blood|1981|p=[https://archive.org/details/redsunsettingbat0000yblo_f0a9/page/7 7]}}: See King's statement in {{harvnb|Quebec Conference|1943|p=448}}. He suggested that the strategic importance of the Marianas could draw the main Japanese fleet out for a major naval battle.{{sfnm|1a1=Goldberg|1y=2007|1pp=[{{Google Books|id=22nSlqbwMskC|pg=PA23|plainurl=yes}} 23]–[{{Google Books|id=22nSlqbwMskC|pg=PA24|plainurl=yes}} 24]|2a1=Heinrichs|2a2=Gallicchio|2y=2017|2p=[https://archive.org/details/implacablefoeswa0000hein/page/92 92]|3a1=Symonds|3y=2022|3p=[{{Google Books|id=hKJnEAAAQBAJ|pg=PA275|plainurl=yes}} 275]|3ps=: See King's reply to Prime Minister of the United Kingdom Winston Churchill in {{harvnb|Quebec Conference|1943|p=409}}.}} King's advocacy gained support from General Henry H. Arnold, Chief of the Army Air Forces, who wanted to use the newly developed B-29 bomber.{{sfn|Y'Blood|1981|p=[https://archive.org/details/redsunsettingbat0000yblo_f0a9/page/7 7]}}

The Marianas could provide secure airfields to sustain a strategic bombing offensive as the islands put much of Japan's population centers and industrial areas within the B-29's {{convert|1600|mi|km|abbr=on}} mile combat radius.{{sfn|Toll|2015|pp= [https://archive.org/details/conqueringtidewa0000toll/page/437 437]–[https://archive.org/details/conqueringtidewa0000toll/page/438 438]}} At the Cairo Conference in November 1943, the Combined Chiefs of Staff supported both MacArthur's offensive in the Southwest Pacific and King's in the Central Pacific,{{sfn|Y'Blood|1981|p=[https://archive.org/details/redsunsettingbat0000yblo_f0a9/page/8 8]}} adding the Marianas as an objective for the Central Pacific offensive and setting 1 October 1944 as the date for their invasion.{{sfn|Matloff|1994|pp=[https://archive.org/details/StrategicPlanningForCoalitionWarfare1943-1944-nsia/page/n396 376–377]}}

File:Battle of Saipan Map.svg

Admiral Chester Nimitz, Commander-in-Chief, Pacific Ocean Areas led the Central Pacific offensive.{{sfn|Smith|1996|pp=[https://archive.org/details/TheApproachToThePhilippines-nsia/page/n20 4–6]}} In January–February 1944, the Marshall Islands were quickly captured and a massive American carrier-based air attack on Truk demonstrated that it could be neutralized and bypassed.{{sfn|Coakley|Leighton|1987|p=[https://archive.org/details/GlobalLogisticsAndStrategy1943-1945/page/n431 406]}} On 12 March 1944, the Joint Chiefs of Staff moved the date of the invasion up to 15 June with the goal of creating airfields for B-29s and developing secondary naval bases.{{sfnm|Hoffman|1950|1p=[https://archive.org/details/saipanthebeginni00wash/page/19 19]|

Y'Blood|1981|2p=[https://archive.org/details/redsunsettingbat0000yblo_f0a9/page/12 12]}} Nimitz updated the plans for the Central Pacific offense, codenamed Granite II, and set the invasion of the Marianas, codenamed Forager,{{sfn|Shaw|Nalty|Turnbladh|1989|p= [https://archive.org/details/historyofusmarin03usma/page/236 236]}} as its initial objective.{{sfn|Y'Blood|1981|p=[https://archive.org/details/redsunsettingbat0000yblo_f0a9/page/7 7]}} Saipan would be the first assault.{{sfn|Shaw|Nalty|Turnbladh|1989|p= [https://archive.org/details/historyofusmarin03usma/page/236 236]}}

The Japanese Imperial War Council established the "{{ill|Absolute National Defense Zone|jp|絶対国防圏}}", Zettai Kokubōken) in September 1943, which was bounded by the Kuril Islands, Bonin Islands, the Marianas, Western New Guinea, Malaya, and Burma.{{sfnm|Smith|2006|1pp=[https://archive.org/details/carrierbattlesco0000smit/page/209 209–211]|Tanaka|2023|2loc=Widening the War into the Asia-Pacific Theatre of World War II, The Third Stage §5}} This line was to be held at all costs if Japan was to win the war.{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA2|plainurl=yes}} 2]|Hiroyuki| 2022|2pp=155–156|Noriaki|2009|3pp=97–99}} The Marianas were considered particularly important to protect as their capture would put Japan within bombing range of the B-29 bomber{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA2|plainurl=yes}} 2]|Wetzler|2020|2p=[{{Google books|id=P6rFDwAAQBAJ|pg=PA32|plainurl=yes}} 32]}} and allow the Americans to interdict the supply routes between the Japanese home islands and the western Pacific.{{sfn|Heinrichs|Gallicchio|2017||p=[https://archive.org/details/implacablefoeswa0000hein/page/92 92]}}

The Imperial Japanese Navy planned to hold the defense line by defeating the United States fleet in a single decisive battle,{{sfn|Morison|1981|pp=[https://archive.org/details/newguineamariana0008samu/page/12 12–14]}} after which, the Americans were expected to negotiate for peace.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA2|plainurl=yes}} 2]}} The Japanese Submarine Fleet (6th Fleet), commanded by Vice Admiral Takeo Takagi whose headquarters was on Saipan,{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/222 222]}} would screen the line.{{sfn|Murfett|2008|p=[{{Google books|id=Jqx9AgAAQBAJ|pg=PA337|plainurl=yes}} 337]}} Any American attempt to breach this line was to serve as the trigger to start the battle.{{sfnm|Hornfischer|2016|1p=[https://archive.org/details/fleetatfloodtide0000horn/page/66 66]|Willoughby|1994|2pp=[https://archive.org/details/ReportsOfGeneralMacarthurJapaneseOperations-nsia/page/n267 250–251]|

Morison|1981|3p=[https://archive.org/details/newguineamariana0008samu/page/94 94]}} The defense forces in the attacked area would attempt to hold their positions while the Japanese Combined Fleet struck the Americans, sinking their carriers with land-based aircraft and finishing the fleet off with surface ships.{{sfn|Shaw|Nalty|Turnbladh|1989|pp=[https://archive.org/details/historyofusmarin03usma/page/220 220–221]}} As part of this plan the Japanese could deploy over 500 land-based planes – 147 of them immediately in the Marianas – that made up the 1st Air Fleet under the command of Vice Admiral Kakuji Kakuta whose headquarters was on Tinian.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/234 234]}}

File:From Mount Tapochau.jpg looking southwest, 2017: Aslito Field is on the left, Charan Kanoa and invasion beaches are left of center, and Garapan is on the right|upright=1.2|alt=panorama of Saipan. There are green hills in the foreground, towns and beaches in the midground, sea and clouds in the distance.]]

Saipan and the other Mariana Islands were claimed as Spanish possessions by the conquistador Miguel López de Legazpi in 1565.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/148 148]}} After Spain's defeat in the Spanish-American War, Saipan was sold to Germany in 1899.{{sfn|Cloud|Schmidt|Burke|1956|p=4}} The island was occupied by the Japanese in 1914 during World War I, who made it the administrative center for the Mariana Islands – Saipan, Tinian and Rota – that were part of Japan's South Seas Mandate.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA7|plainurl=yes}} 7]}}

Saipan has a tropical marine climate with a mean annual temperature of {{convert|85|F|C}} in the lowlands and {{convert|78|F|C}} in the highlands. Though the island has a mean rainfall between {{convert|81|in|cm}} and {{convert|91|in|cm}} inches per year, the rainy season does not begin until July.{{sfn|Cloud|Schmidt|Burke|1956|p=6}}

Unlike the small, flat coral atolls of the Gilberts and Marshalls,{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/62 62]}}

Saipan is a volcanic island with diverse terrain well suited for defense.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/29 29]|Goldberg|2007|2p=[{{Google Books|id=22nSlqbwMskC|pg=PA30|plainurl=yes}} 30]}}

It is approximately {{convert|47|sqmi|km2|0|abbr=on}},{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=11|plainurl=yes}} 11]}}{{efn|Post-war estimates range from 46{{sfn|USACE|2022|p=3}} square miles to 48.{{sfn|Cloud|Schmidt|Burke|1956|p=1}} {{harvnb|Hallas|2019|loc=p. 479, fn 5}} points out that most historians describing the battle state that the island is substantially larger. For example, {{harvnb|McManus|2021|p=[{{Google books|id=BOwmEAAAQBAJ|pg=PA339|plainurl=yes}} 339]}}, {{harvnb|Shaw|Nalty|Turnbladh|1989|p= [https://archive.org/details/historyofusmarin03usma/page/238 238]}} state that it is 72, {{harvnb|Goldberg|2007|p=[{{Google Books|id=22nSlqbwMskC|pg=PA38|plainurl=yes}} 38]}} says 75, and {{harvnb|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/29 29]}} says 85 square miles.}}

and has a volcanic core surrounded by limestone.{{sfn|Cloud|Schmidt|Burke|1956|p=1}} In the center of the island is Mount Tapotchau, which rises to {{convert|1554|ft|m|0|abbr=on}}. From the mountain, a high ridge ran northward about {{convert|7|mi|km}} to Mount Marpi.{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/29 29]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p= [https://archive.org/details/historyofusmarin03usma/page/238 238]}} This area was filled with caves and ravines concealed by forest and brush,{{sfn|Goldberg|2007|p=[{{Google Books|id=22nSlqbwMskC|pg=PA30|plainurl=yes}} 30]}} and the mountainous terrain would force tanks to stay on the island's few roads, which were poorly constructed.{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA138|plainurl=yes}} 138]}}

The southern half of the island was where the principal airfield of the Marianas, Aslito Field, was located.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/54 54]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/152 152]}} It served as a repair stop and transit hub for Japanese aircraft headed toward other parts of the Pacific.{{sfnm|Goldberg|2007|1pp=[{{Google Books|id=22nSlqbwMskC|pg=PA30|plainurl=yes}} 30]–[{{Google Books|id=22nSlqbwMskC|pg=PA31|plainurl=yes}} 31]|Hallas|2019|2pp=[{{Google books|id=kg2QDwAAQBAJ|pg=PA8|plainurl=yes}} 8]–[{{Google books|id=kg2QDwAAQBAJ|pg=PA9|plainurl=yes}} 9]|Morison|1981|3p=[https://archive.org/details/newguineamariana0008samu/page/152 152]}}

This half of the island was flatter but covered with sugar cane fields{{sfn|Shaw|Nalty|Turnbladh|1989|p= [https://archive.org/details/historyofusmarin03usma/page/238 238]}} because the island's economy became focused on sugar production after the Japanese government had taken over Saipan from Germany in 1914.{{sfnm|Hoffman|1950|1p=[https://archive.org/details/saipanthebeginni00wash/page/7 7]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/151 151]}} Seventy percent of Saipan's acreage was dedicated to sugar cane.{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=PA7|plainurl=yes}} 7]}} It was so plentiful that a narrow-gauge railway was built around the perimeter of the island to facilitate its transportation.{{sfn|Astroth|2019|p =38}} These cane fields were an obstacle to attackers: they were difficult to maneuver in and provided concealment for the defenders.{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ|pg=PA129|plainurl=yes}} 129]}}

Saipan was the first island during the Pacific War where the United States forces encountered a substantial Japanese civilian population,{{sfnm|Sheeks|1945|1p=112|Toll|2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/508 508]}} and the first where U. S. Marines fought around urban areas.{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=PR7|plainurl=yes}} vii]}} Approximately 26,000{{sfn|American Memorial Park|2021}} to 28,000{{sfn|Astroth|2019|p=166}} civilians lived on the island, primarily serving the sugar industry.{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=PA7|plainurl=yes}} 7]}} The majority of them were Japanese subjects, most of whom were from Okinawa and Korea; a minority were Chamorro people.{{sfn|Astroth|2019|p=38}} The largest towns on the island were the administrative center of Garapan, which had a population of 10,000, Charan Kanoa, and Tanapag. They were on the western coast of the island, which was where the best landing beaches for an invasion were.{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ|pg=PA129|plainurl=yes}} 129]}}

{{Further|Battle of Saipan order of battle|Central Marianas naval order of battle}}

File:LVTs move toward Saipan, past bombarding cruisers, on 15 June 1944 (80-G-231838).jpgs heading for shore on 15 June. {{USS|Birmingham|CL-62|2}} in foreground; the cruiser firing in the distance is {{USS|Indianapolis|CA-35|2}}|alt=Two cruisers, one in front left foreground,a second in the upper distance is firing. Amphibious vehicles are headed to the right.]]

Nimitz, the commander of the Pacific Fleet, assigned Admiral Raymond Spruance, commander of the Fifth Fleet, to oversee the operation. Vice Admiral Richmond K. Turner, Commander, Joint Amphibious Forces (Task Force 51) oversaw the overall organization of the amphibious landings of the Mariana Islands; he also oversaw the tactical command of the landing on Saipan as Commander, Northern Attack Force (TF 52).{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/239 239]}} Once the amphibious landings were completed, Lieutenant General Holland M. Smith, Commanding General, Expeditionary Troops (Task Force 56), would oversee the ground forces for all of Forager; he would also oversee the ground combat on Saipan as Commander, Northern Troops and Landing Force.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/39 39]|Hallas|2019|2pp=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA18|plainurl=yes}} 18–19]}}

The Northern Troops and Landing Force was built around the V Amphibious Corps,{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA17|plainurl=yes}} 17]}} which consisted of the 2nd Marine Division commanded by Major General Thomas E. Watson and 4th Marine Division commanded by Major General Harry Schmidt.{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/37 37]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/240 240]}}

The 27th Infantry Division commanded by Major General Ralph C. Smith was held as the Expeditionary Troops reserve for use anywhere in the Marianas.{{sfnm|Goldberg|2007|1pp=[{{Google Books|id=22nSlqbwMskC|pg=PA39|plainurl=yes}} 39–40]|Crowl|1993|2pp=[https://archive.org/details/CampaignInTheMarianas/page/36 36–37]}} Over 60,000 troops were assigned to the assault.{{efn|{{harvnb|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/36 36]}} puts the total at 66,779; {{harvnb|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/253 253] put it at 71,034}} }} Approximately 22,000 were in each Marine division and 16,500 in the 27th Infantry Division.{{sfnm|1a1=Hallas|1y=2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA31|plainurl=yes}} 31]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/240 240]}}

The invasion fleet, consisting of over 500 ships and 300,000 men,{{efn|{{harvnb|Morison|1981|pp=[https://archive.org/details/newguineamariana0008samu/page/160 160–162]}} puts the number of ships at 535 and mentions that the four and a half divisions

of ground combat troops numbered 127,571; {{harvnb|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/457 457]}} puts the number of ships at 600 and the number of men at 600,000, which may include naval personnel.}} got underway days before the Allied forces in Europe invaded France in Operation Overlord on 6 June 1944.{{sfnm|Morison|1981|1pp=[https://archive.org/details/newguineamariana0008samu/page/160 160–162]|Toll|2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/457 457]}} It was launched from Hawaii, briefly stopping at Eniwetok and Kwajalein before heading for Saipan. The Marine divisions left Pearl Harbor on 19–31 May and rendezvoused at Eniwetok on 7–8 June; the 27th Infantry Division left Pearl Harbor on 25 May and arrived at Kwajalein on 9 June.{{sfn|Morison|1981|pp=[https://archive.org/details/newguineamariana0008samu/page/170 170–172]}} The fifteen aircraft carriers of the Fast Carrier Task Force (Task Force 58) commanded by Vice Admiral Marc A. Mitscher,{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/174 174]}} which would provide support for the invasion, left Majuro for Saipan on 6 June.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/172 172]}}

File:Saipan flamethrower (cropped).jpg with a Ronson flamethrower, incinerates a Japanese pillbox on Saipan, June 1944|alt=tank shooting flame into foliage and pillbox, creating a plume of smoke.]]

The invasion force included 150 tanks, over 100 of which were M4 Sherman tanks.{{sfn|Report of Capture of Marianas|1944|loc=[https://archive.org/details/turner-report/page/n292 Annex 2, Enclosure N]|ps=: Quartermaster's reports for the 2nd Marine Division's, 4th Marine Division's, and 27th Infantry Division's total to 101 medium tanks, 57 light tanks, 24 light mechanized flamethrowers, and 6 medium tanks with bulldozers.}} The M4 Sherman tank was superior to the medium tank used by the Japanese, the Type 97.{{sfn|Zaloga|2012|p=[{{Google Books|id=TOG6CwAAQBAJ|pg=PA6|plainurl=yes}} 6]}} It was primarily used to support infantry and was considered one of the most effective weapons for destroying enemy emplacements.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/575 575]}} Flame throwers were extensively used. Smith had seen the need for motorized flamethrowers and had requested that the Army's Chemical Warfare Service (CWS) in Hawaii install them in M3 Stuart tanks. Seabees with the CWS had 24 tanks, nicknamed "Satans", converted to flamethrowing in time for the invasion. They were very effective for destroying pillboxes, cave defenses, buildings, canefields, and brush.{{sfn|Kleber|Birdsell|1990|p=[https://archive.org/details/CMHPub10-3-nsia/page/n577 560]}}

File:Battle of Saipan - Japanese beach defense GAG01-modified (cropped).jpg coastal defense gun found on Saipan after the battle|alt=cannon in profile facing left with ocean in the background.]]

American intelligence had estimated that there would be between 15,000 and 18,000 Japanese troops on Saipan at the time of the invasion.{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA55|plainurl=yes}} 55]|Hoffman|1950|2p=[https://archive.org/details/saipanthebeginni00wash/page/26 26]}} In actuality, there were double that number.{{sfn|Bisno|2019}} Nearly 32,000 Japanese military personnel were on the island, including 6,000 naval troops.{{sfn|Heinrichs|Gallicchio|2017|p=[https://archive.org/details/implacablefoeswa0000hein/page/92 92]}} The two major army units defending the island were the 43rd Division commanded by Lieutenant General Yoshitsugu Saitō and the 47th Independent Mixed Brigade commanded by Colonel Yoshira Oka.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA55|plainurl=yes}} 55]}} Both units were assigned to the Thirty-First Army under the overall command of Lieutenant General Hideyoshi Obata.

The Japanese hurriedly reinforced the island before the invasion, but many of the troop transports were sunk by U.S. submarines.{{sfn|Goldberg|2007|p=[{{Google Books|id=22nSlqbwMskC |pg=PA31|plainurl=yes}} 31–32]}} For example, five of the seven ships transporting the 43rd Division were sunk.{{sfnm|1a1=Heinrichs|1a2=Gallicchio|1y=2017|1pp=[https://archive.org/details/implacablefoeswa0000hein/page/93 93–94]|2a=Toland|2y=2003|2p=[https://archive.org/details/risingsundecline0000tola/page/484 484]}} Most of the troops were saved, but the majority of their equipment–including hats and shoes–was lost, reducing their effectiveness.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA31|plainurl=yes}} 31]}} Many soldiers were the stranded survivors of sunken ships headed to other islands.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA29|plainurl=yes}} 29]}} There were about 80 tanks on the island, substantially more than the Americans had encountered in previous battles with the Japanese.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA56|plainurl=yes}} 56]}}

The Japanese defenses were set up to defeat an invading force on Saipan's beaches, where the invading troops were most vulnerable.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/62 62–63]}} These defenses focused on the most likely invasion locations, the western beaches south of Garapan.{{sfn|McManus|2021|pp=[{{Google books|id=HvBmAAAAMAAJ|pg=PA339|plainurl=yes}} 339]–[{{Google books|id=HvBmAAAAMAAJ|pg=PA339|plainurl=yes}} 340]}} This made the defenses weak. If an invading force broke through the beach defenses, there was no organized fallback position: the Japanese troops would have to rely on Saipan's rough terrain, especially its caves, for protection.{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ|pg=PA139|plainurl=yes}} 139]}} The original plans called for a defense in depth that fortified the entire island{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ|pg=PA129|plainurl=yes}} 139]}} if time allowed,{{sfn|Hallas|2019|p=57}} but the Japanese were unable to complete their defenses by the time of the invasion. Much of the building material sent to Saipan, such as concrete and steel, had been sunk in transit by American submarines,{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/62 62]}} and the timing of the invasion surprised the Japanese, who thought they had until November to complete their defense.{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ|pg=PA139|plainurl=yes}} 139]}} As of June, many fortifications remained incomplete, available building materials were left unused, and many artillery guns were not properly deployed.{{sfn|Goldberg|2007|p=[{{Google Books|id=22nSlqbwMskC|pg=PA35|plainurl=yes}} 35]}}

Japanese leadership on the island suffered from poor command coordination.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/57 57–58]}} Although Vice Admiral Chūichi Nagumo, Commander of the Central Pacific Area Fleet, had nominal oversight of the defenses in the Central Pacific, Obata refused to subordinate his army command to a naval officer.{{sfnm|1a1=Shaw|1a2=Nalty|1a3=Turnbladh|1y=1989|1p=[https://archive.org/details/historyofusmarin03usma/page/256 256]|2a1=McManus|2y=2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA338|plainurl=yes}} 338]}} Because Obata was on Guam and away from his Saipan headquarters when the invasion started, command of Saipan's army units fell to Saitō, who was the senior army officer on the island.{{sfnm|McManus|2021|1p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA338|plainurl=yes}} 338]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/167 167]}} Obata's chief of staff, Major General Keiji Igeta, maintained a separate headquarters that was often out of touch with Saitō.{{sfnm|Hallas|2019|1pp=139, 197|McManus|2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA339|plainurl=yes}} 339]}}

File:Inferno by William F. Draper.jpg of the destruction of the sugar mill at Charan Kanoa on 15 June (Navy Art Collection, Naval History and Heritage Command) |alt=Building on left with orange flames and a plume stretching to the right top corner. There are leafless trees and soldiers can be seen looking on the lower left of the picture.]]

On 11 June, over 200 F6F Hellcats from the Fast Carrier Task Force launched a surprise attack on Japanese airfields in Saipan and Tinian,{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/73 73]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2pp= [https://archive.org/details/historyofusmarin03usma/page/253 253–254]|3a1=Toll|3y=2015|3p=[https://archive.org/details/conqueringtidewa0000toll/page/462 462]}} putting approximately 130 Japanese aircraft out of operation{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/73 73]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2pp= [https://archive.org/details/historyofusmarin03usma/page/253 253–254]}} at the cost of 11 American aircraft.{{sfnm|Hallas|2019|1p= [{{Google Books|id=kg2QDwAAQBAJ|pg=PA68|plainurl=yes}} 68]|Toll|2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/462 462]|2ps=:{{harvnb|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/254 254]}} puts the number at 11.}}

The attack destroyed most of the 1st Air Fleet's land-based planes that had been deployed to defend the Marianas,{{sfn|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/463 463]}} and gave the Americans air superiority over Saipan.{{sfnm|1a1=Cressman|1y=2000|1p=[https://archive.org/details/TheOfficialChronologyOfTheUSNavyInWorldWarII-nsia/page/n493 495]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p= [https://archive.org/details/historyofusmarin03usma/page/253 253–254]}} Planes from the task force continued their attacks until 14 June,{{sfn|Cressman|2000|p=[https://archive.org/details/TheOfficialChronologyOfTheUSNavyInWorldWarII-nsia/page/n494 496]}} harassing fields, bombing military targets, and burning cane fields on the southern half of Saipan.{{sfn|Crowl|1993|p= [https://archive.org/details/CampaignInTheMarianas/page/73 73]}} By the end of the week, the 1st Air Fleet had been reduced to about 100 aircraft.{{sfn|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/463 463]}}

On 13 June, seven fast battleships and 11 destroyers under Vice Admiral Willis Lee began the naval bombardment of Saipan.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/74 74]|Toll|2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/463 463]}} Most of these battleships' crews had not been trained in shore bombardment and the ships fired from more than {{convert|5.5|miles|km|abbr=on}} to avoid potential minefields. The bombardment damaged much of Garapan and Charan Kanoa, but it was relatively ineffective at destroying the island's defenses.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/74 74]}} The following day, seven older battleships, 11 cruisers, and 26 destroyers{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/254 254]}} commanded by Rear Admiral Jesse B. Oldendorf continued the shelling.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/180 180]}} These crews were trained in shore bombardment,{{sfn|Hornfischer|2016|pp=[https://archive.org/details/fleetatfloodtide0000horn_b3y7/page/88 88]-[https://archive.org/details/fleetatfloodtide0000horn_b3y7/page/89 89]}} and moved closer to shore because the sea was found to be free of mines.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/76 76]}} This bombardment eliminated many emplaced anti-aircraft positions,{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/76 76]}} but it too failed to destroy most of the beach defenses.{{sfnm|Goldberg|2007|1p=[{{Google Books|id=22nSlqbwMskC |pg=PA54|plainurl=yes}} 54]|Morison|1981|2pp=[https://archive.org/details/newguineamariana0008samu/page/182 182–183]}}

File:Red Beach -2.jpg on Red Beach at 13:00 on 15 June.|alt=uneven beach in foreground littered with equipment, Marines, and amphibious vehicle in the distance]]

15 June was D-Day for the amphibious landing,{{sfn|Goldberg|2007|p=[{{Google Books|id=22nSlqbwMskC|pg=PA3|plainurl=yes}} 3]}} which began around 08:40.{{sfnm|Hallas|2019|1p=96|Hoffman|1950|2pp=[https://archive.org/details/saipanthebeginni00wash/page/46 46–47]|McManus|2021|3p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA348|plainurl=yes}} 348]|Schmidt|1944|4p=11}} Naval and aerial bombardments in preparation for the landings began earlier in the morning,{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/202 202]}}

disrupting the Japanese communications network.{{sfnm|Hornfischer|2016|1p=[https://archive.org/details/fleetatfloodtide0000horn/page/136 136]

|McManus|2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA346|plainurl=yes}} 346]}}

The guns of the warships would provide continuous supporting fire throughout the day.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/202 202]}}

The V Amphibious Corps landed on the southwest beaches of Saipan.{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA131|plainurl=yes}} 131]}} The 2nd Marine Division landed on two beaches, named Red and Green, of Charan Kanoa, and the 4th Marine Division landed on the beaches named Blue and Yellow south of the town.{{sfnm|Hoffman|1950|1p=[https://archive.org/details/saipanthebeginni00wash/page/27 27]

|Lacey|2013|2p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA131|plainurl=yes}} 131]}} Approximately 700 amphibious vehicles participated in the assault,{{sfnm|Hoffman|1950|1p=[https://archive.org/details/saipanthebeginni00wash/page/50 50]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/202 202]|Schmidt|1944|3p=11}} including 393 amphibious tractors (LVTs) and 140 amphibious tanks.{{sfnm|Gugeler|1945|1p=3|Hallas|2019|2p=96}} Within 20 minutes, there were around 8,000 men on the beaches.{{sfnm|Hallas|2019|1p=127|Millett|1980|2p=[https://archive.org/details/semperfidelishis0000mill/page/412 412]|Toll|2015|3p=[https://archive.org/details/conqueringtidewa0000toll/page/466 466]}}

The beaches were fortified by trenches and a few pillboxes,{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/45 45]}} but the landings were mainly contested by constant and intensive fire by Japanese artillery, mortars,{{sfn|McManus|2021|p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA348|plainurl=yes}} 348]}} and machine guns.{{sfn|Heinrichs|Gallicchio|2017|p=[https://archive.org/details/implacablefoeswa0000hein/page/92 92]}} The Japanese had concentrated at least 50 large artillery pieces on the high ground—including at least 24 105-mm howitzers and 30 75-mm field pieces—around the invasion beaches. Many were deployed on reverse slopes,{{sfn|

Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/93 93]}} and pennants had been placed on the beach for accurate ranging.{{sfnm|1a1=Hallas|1y=2019|1p=90|2a1=Toll|2y=2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/466 466]|3a1=Shaw|3a2=Nalty|3a3=Turnbladh|3y=1989|3p=[https://archive.org/details/historyofusmarin03usma/page/263 263]}} The Americans suffered over 2,000 casualties,{{sfnm|Hallas|2019|1p=140

|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA145|plainurl=yes}} 145]

|McManus|2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA350|plainurl=yes}} 350]}}{{efn|{{Harvnb|McManus|2021|p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA350|plainurl=yes}} 350]}} estimates 2,500, {{harvnb|Heinrichs|Gallicchio|2017|p=[https://archive.org/details/implacablefoeswa0000hein/page/95 95]}} put the estimate near 3,500. In his after battle report, Major General Harry Schmidt, Commander of the 4th Marine Division, put the casualties for the first two days at 3,500, which is about 20% of the casualties suffered during the entire battle.{{sfn|Schmidt|1944|p=11}}}} the majority were due to the artillery and mortar fire.{{sfnm|Hallas|2019|1p=140|Hoffman|1950|2p=[https://archive.org/details/saipanthebeginni00wash/page/50 50]}} Additionally, 164 amphibious tractors and amphibious tanks, about 40% of those engaged during the day, had been destroyed or damaged.{{sfn|Gugeler|1945|p= 27}}

File:Saipan June 15-crop.png

By the end of the day, the Marines managed to establish a bridgehead about {{convert|5.5|mi|km|0|abbr=on}} along the beach and {{convert|0.5|mi|km|0|abbr=on}} inland,{{sfnm|Hallas|2019|1p=141|Lacey|2013|2p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA145|plainurl=yes}} 145]|McManus|2021|3p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA350|plainurl=yes}} 350]}} and had unloaded artillery and tanks.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/92 92]}}

The bridgehead was only about two-thirds the size of the planned objective,{{sfn|Lacey|2013|p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA145|plainurl=yes}} 145]}} the two Marine divisions were separated by a wide gap just north of Charan Kanoa,{{sfnm|Hallas|2019|1p=140|Hornfischer|2016|2p=[https://archive.org/details/fleetatfloodtide0000horn/page/142 142]|Lacey|2013|3p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA145|plainurl=yes}} 145]}}

and the Japanese artillery remained intact on the high ground surrounding the beach.{{sfnm|Hallas|2019|1p=140|Toll|2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/466 466]}}

When darkness fell, Saito launched a series of night attacks to push the Americans back into the sea.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/95 95]|Hallas|2019|2p=145}} The Japanese launched repeated counterattacks during the night and the early hours of the following morning,{{sfnm|Crowl|1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/95 95–96]|Hoffman|1950|2pp=[https://archive.org/details/saipanthebeginni00wash/page/n95 71–75]}} mostly by poorly coordinated small units.{{sfn|Goldberg|2007|p=88}} All the attacks were repulsed,{{sfnm|1a1=Harmsen|1y=2021|1p=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA62|plainurl=yes}} 62]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2pp=[https://archive.org/details/historyofusmarin03usma/page/278 278–279]}} partly by the firepower provided by the tanks and artillery that had been unloaded during the day as well as by American warships that illuminated the combat areas with star shells.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/95 95–96]}}

File:USMC-M-Saipan-p891 (cropped).jpg knocked out in 17 June attack|alt=tank in profile facing right with hills in background]]

On 16 June, Holland Smith committed his reserves to reinforce the beachhead, ordering two of the three regiments of the 27th Infantry Division—the 165th and the 105th—to land.{{sfnm|Crowl|1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/99 99–100]|Hallas|2019|2pp=171–173|Goldberg|2007|3p=142}} He proposed to indefinitely postpone the 18 June invasion of Guam.{{sfnm|Morison|1981|1pp=[https://archive.org/details/newguineamariana0008samu/page/202 202–203]|Toll|2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/467 467]}}{{efn|The invasion of Guam did not occur until 21 July.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/339 339}}}} The two Marine divisions on Saipan spent most of the day consolidating the beachhead.{{sfnm|Crowl|1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/97 97–98]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/203 203]}} The 2nd Marine Division began to close the gap between the two divisions north of Charan Kanoa, and the 4th Marine Division cleared the area around Aginan point on the southwest of the Island.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/96 96–97]}}

During the night, Saitō launched a tank assault on the flank of the beachhead just north of Charan Kanoa with approximately 35 Type 97 medium tanks and Type 95 light tanks{{efn|{{harvnb|Hallas|2019|p=165}} puts the number between 24 and 32; {{harvnb|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/98 98]}} puts the number at no less than 37;

{{harvnb|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/86 86]}}, {{harvnb|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/202 202]}} and {{harvnb|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/284 284]}} put the number at 44.}} and about 1,000 soldiers.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/97 97]|Hallas|2019|2p=164}} The attack was poorly coordinated.{{sfn|Hoffman|1950|pp=[https://archive.org/details/saipanthebeginni00wash/page/86 86–87]}} Nagumo's naval troops, who were supposed to be part of the attack, did not cooperate.{{sfn|Shaw|Nalty|Turnbladh|1989|pp=[https://archive.org/details/historyofusmarin03usma/page/284 284–285]}} The attack was broken up by bazookas, 37 mm anti-tank guns, M4 Sherman tanks, and self-propelled 75 mm howitzers.{{sfnm|1a1=Heinrichs|1a2=Gallicchio|1y=2017|1p=[https://archive.org/details/implacablefoeswa0000hein_u8l8/page/96 96]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/285 285]}}

Around 31 Japanese tanks were destroyed.{{sfnm|1a1=Hallas|1y=2019|1p=170|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/286 286]}}

File:Soldiers of 27th Infantry moving inland, Saipan 1944.webp moving inland after landing on 16 June|alt=two columns of American soldiers marching toward right of camera]]

In the following days, the 2nd Marine Division on the northern half of the bridgehead cleared the area around Lake Susupe{{sfn|Hoffman|1950|pp=[https://archive.org/details/saipanthebeginni00wash/page/92 92–94]}} and reached the objectives for the first day of the invasion,{{sfn|Goldberg|2007|pp=105–106|}} and slowly moved north toward Garapan and Mount Tapotchou.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/108 108–109], [https://archive.org/details/CampaignInTheMarianas/page/115 115–116], [https://archive.org/details/CampaignInTheMarianas/page/154 154]}} In the southern half of the bridgehead, the 4th Marine Division began their advance on Aslito Field. On 18 June, the two regiments of the 27th Infantry Division, which was now fighting as a unit,{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/111 111]}} captured the field{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/295 295]}} as the Japanese withdrew to Nafutan Point in the southeast of the island.{{sfnm|Goldberg|2007|1p=145–146|Hallas|2019|2p=192}} The 4th Marine Division had reached the island's eastern coast, cutting off the Japanese troops at Nafutan Point from the north.{{sfn|Shaw|Nalty|Turnbladh|1989|pp=[https://archive.org/details/historyofusmarin03usma/page/294 294–295]}} During this time, Saitō was falsely rumored to have been killed.{{sfnm|1a1=Hallas|1y=2019|1p=170|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/292 292]}} Igeta erroneously reported Saitō's death to Tokyo, though he corrected the report later.{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/n127 101]}}

Holland Smith ordered the 27th Infantry Division to quickly capture Nafutan Point but it was unable to do so.{{sfn|Goldberg|2007|pp=[{{Google Books|id=22nSlqbwMskC |pg=PA148|plainurl=yes}} 148]–149}} Smith had estimated that there were no more than 300 Japanese soldiers in the area, but there were more than 1,000 defending the rough terrain.{{sfnm|Hallas|2019|1p=270|Lacey|2013|2p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA149|plainurl=yes}} 149]}} The battle for the point would continue for over a week.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/138 138]}}

By 19 June, the Japanese forces on the island had been reduced by about half.{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/166 166]|2a1=Heinrichs|2a2=Gallicchio|2y=2017|2p=[https://archive.org/details/implacablefoeswa0000hein_u8l8/page/111 111]}}

Saitō began withdrawing his troops to a new defensive line in the center of the island.{{sfn|Crowl |1993|p=[https://archive.org/details/CampaignInTheMarianas/page/165 165]}} By this time, the Americans had suffered over 6,000 casualties.{{sfnm|1a1=Hallas|1y=2019|1p=287|1ps=|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/305 305]|2ps=;{{harvnb|Report of Capture of Marianas|1944|loc=[https://archive.org/details/turner-report/page/n257enclosure (K), p.5]}} reports 6,200 casualties on D-Day + 5 (20 June)}} The Marine divisions headed north toward the new Japanese defenses,{{sfnm|Hornfischer|2016|1p=[https://archive.org/details/fleetatfloodtide0000horn/page/208 208]|McManus|2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA348|plainurl=yes}} 348]}} and Holland Smith called for the final reserve of the Expeditionary Forces, ordering the last regiment of the 27th infantry Division, the 106th, to land on Saipan on 20 June.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/164 164–165]}}

{{main article|Battle of Philippine Sea}}

File:TBFs and SB2Cs enroute to attack during the Battle of the Philippine Sea.tif torpedo planes and SB2C Helldiver dive bombers from the Fast Carrier Task Force en route to attack the 1st Mobile Fleet, June 1944 during the Battle of the Philippine Sea|alt=16 planes in profile flying to the right. Cumulus clouds and ocean at the bottom of the picture.]]

Once Admiral Soemu Toyoda, Commander-in-Chief of the Combined Fleet, was certain that Saipan was the target of an invasion, he initiated his response.{{sfn|Hornfischer|2016|p=[https://archive.org/details/fleetatfloodtide0000horn/page/86 86]}}

Less than a half hour after the start of the amphibious invasion,{{sfn|Harmsen|2021|p=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA63|plainurl=yes}} 63]}} he announced the implementation of Operation A-Go,{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA147|plainurl=yes}} 147]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/221 221]}} the Japanese Navy's current plan to destroy the American fleet.{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA1|plainurl=yes}} 1]|Hopkins|2008|2p=[https://archive.org/details/pacificwarstrate0000hopk/page/228 288]|Harmsen|2021|3p=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA63|plainurl=yes}} 63]}} He then sent a message to the entire fleet that repeated Admiral Heihachirō Tōgō's speech before Japan's decisive naval battle against Russia at Tsushima in 1905, which in turn echoed Horatio Nelson's signal at the Battle of Trafalgar in 1805:{{sfn|Harmsen|2021|p=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA63|plainurl=yes}} 64]}} "The fate of the Empire rests upon this single battle. Every man is expected to do his utmost."{{sfnm|Harmsen|2021|1p=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA64|plainurl=yes}} 64]|Willoughby|1994|2p= [https://archive.org/details/ReportsOfGeneralMacarthurJapaneseOperations-nsia/page/n309 292]|Morison|1981|3p=[https://archive.org/details/newguineamariana0008samu/page/262 262]}}

Originally, the Japanese Navy sought to have the battle take place in the Palaus or Western Carolines,{{sfnm|1a1=Hallas|1y=2019|1pp=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA73|plainurl=yes}} 73]–[{{Google Books|id=kg2QDwAAQBAJ|pg=PA74|plainurl=yes}} 74]|2a1=Morison|2y=1981|2p=[https://archive.org/details/newguineamariana0008samu/page/215 215]|

3a1=Shaw|3a2=Nalty|3a3=Turnbladh|3y=1989|3p=[https://archive.org/details/historyofusmarin03usma/page/221 221]}} and MacArthur's invasion of Biak had led them to believe that they could lure the American fleet there.{{sfnm|Morison|1981|1p=[https://archive.org/details/newguineamariana0008samu/page/220 220]|Toll|2015|2pp=[https://archive.org/details/conqueringtidewa0000toll/page/454 454–455]}} After the preinvasion bombardment of Saipan, Toyoda guessed Saipan was the target and ordered Vice Admiral Matome Ugaki who commanded the super battleships Yamato and Musashi to rendezvous with Vice Admiral Jisaburō Ozawa, commander of the 1st Mobile Fleet and to rendezvous in the Philippine Sea to attack the American fleet around Saipan.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/121 121]|Hopkins|2008|p=[https://archive.org/details/pacificwarstrate0000hopk/page/228 228]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/221 221]}} The Japanese fleet, which had 9 aircraft carriers, 5 battleships, and nearly 500 airplanes was outnumbered by the American fleet,{{sfn|Winton|1993|p=[https://archive.org/details/ultrainpacificho0000wint/page/167 167]}} which had 16 aircraft carriers, 7 battleships, and almost 1,000 airplanes.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/233 233]}}

The Japanese thought they had some advantages: the longer range of the Japanese planes would allow them the opportunity to strike the Americans without fear of immediate retaliation,{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/233 233]}} the availability of airbases on the Marianas would give the carrier planes a place to land and quickly rearm for further strikes,{{sfn|Harmsen|2021|p=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA63|plainurl=yes}} 63]}} and Kakuta was incorrectly assumed to have 500 additional land-based planes available.{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA147|plainurl=yes}} 147]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/219 219]|Toyoda|1944|3p=[https://archive.org/details/campaignsofpacif46unit/page/229 229]}}

The American transports continued to unload supplies and reinforcements throughout 17 June. The following day, the transports sailed east toward safety while the warships set off for battle with the Japanese fleet. On 19–20 June, the fleets fought an aircraft carrier battle.{{sfn|McManus|2021|pp=351–352}} The Japanese struck first,{{sfn|Hallas|2019|p=206}} launching four large air attacks on the American fleet.{{sfnm|1a1=Hopkins|1y=2008|1pp=[https://archive.org/details/pacificwarstrate0000hopk/page/228 228–229]|2a1=Morison|2y=1981|2pp=[https://archive.org/details/newguineamariana0008samu/page/263 263–274]|3a1=Shaw|3a2=Nalty|3a3=Turnbladh|3y=1989|3p=[https://archive.org/details/historyofusmarin03usma/page/299 299]}} The Japanese aviators were inexperienced and outnumbered: very few of the anticipated land-based planes were available,{{sfnm|Goldberg|2007|1p=[{{Google Books|id=22nSlqbwMskC |pg=PA102|plainurl=yes}} 102]|Harmsen|2021|2pp=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA65|plainurl=yes}} 65]–[{{Google Books|id=9fM5EAAAQBAJ|pg=PA66|plainurl=yes}} 66]}} and those that were had little effect.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/298 298]}}

The Japanese lost almost 500 planes{{sfn|Hornfischer|2016|p=[https://archive.org/details/fleetatfloodtide0000horn/page/232 232]}} and almost all their aviators;{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/321 321]}} their carrier forces were left with only 35 operable aircraft.{{sfn|

Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/497 497]}} The Americans lost about 130 planes{{sfn|Hornfischer|2016|p=[https://archive.org/details/fleetatfloodtide0000horn/page/232 232]}} and 76 aviators.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/321 321]}} An American counterstrike sank a Japanese carrier, and American submarines sank two others, including Ozawa's flagship Taihō.{{sfn|Harmsen|2021|pp=[{{Google Books|id=9fM5EAAAQBAJ|pg=PA65|plainurl=yes}} 65]–[{{Google Books|id=9fM5EAAAQBAJ|pg=PA66|plainurl=yes}} 66]}} The Japanese submarine fleet failed to play a significant role as well. The invasion forced Takagi to move his headquarters from Garapan into the mountains of Saipan, making his command ineffective.{{sfn|Boyd|Yoshida|2013|p=[{{Google books|id=U2wtWnDBvEgC|pg=PA146|plainurl=yes}} 146]}} Out of 25 submarines deployed for the battle, 17 were sunk.{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/230 230]}} Though defenders on the island didn't know it at the time, the defeat of the Japanese fleet ensured that they would not be reinforced, resupplied or receive further military support.{{sfn|Morison|1981|pp=[https://archive.org/details/newguineamariana0008samu/page/322 322–324]}}

The Japanese command was determined to hold the island at all costs,{{sfn|Goldberg|2007|p=89}} but it would be fighting a losing battle of attrition.{{sfnm|Hallas|2019|1p=268|Lacey|2013|2p=[{{Google Books|id=ScFZAQAAQBAJ |pg=PA149|plainurl=yes}} 149]}}

File:Marines in rough terrain, Saipan 1944.tif typical of central and north Saipan, June 1944|alt=Three soldiers looking away from the camera toward a cave-like fissure.]]

Saitō's new defense line stretched from Garapan on the west coast to the southern slopes of Mount Tapatchou across to Magicienne Bay on the east coast.{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/116 116]|2a1=McManus|2y=2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA356|plainurl=yes}} 356]|3a1=Shaw|3a2=Nalty|3a3=Turnbladh|3y=1989|3p=[https://archive.org/details/historyofusmarin03usma/page/295 295]}} It held most of the island's high ground, which allowed the Japanese to observe American movements, and the rough terrain was filled with caves concealed by brush.{{sfn|Goldberg|2007|pp=156–157}}

The American forces prepared for a frontal assault on Saitō's line using all three divisions.{{sfn|Heinrichs|Gallicchio|2017|pp=[https://archive.org/details/implacablefoeswa0000hein/page/114 114–115]}} The attack began on 22 June. The 2nd Marine Division which was on the western coast moved toward Garapan and Mount Tapatchou; the 4th Marine Division advanced along the eastern coast,{{sfn|Hornfischer|2016|p=[https://archive.org/details/fleetatfloodtide0000horn/page/236 236]}} which created gaps in the lines in the hilly ground between the two divisions.{{sfnm|Hoffman|1950|1p=[https://archive.org/details/saipanthebeginni00wash/page/128 128]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/307 307]}} That evening, the 27th Infantry Division, less the regiment left to reduce Nafutan point,{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/305 305]}} was ordered to move up into the difficult terrain between the two Marine divisions.{{sfn|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/498 498]}}

The next day, the Marine divisions on the flanks made progress, but the 27th Infantry Division, which started its attack late, stalled in its assault on a valley surrounding a low lying ridge that was defended by about 4,000 Japanese soldiers.{{sfnm|Hornfischer|2016|1p=[https://archive.org/details/fleetatfloodtide0000horn/page/238 238]|McManus|2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA362|plainurl=yes}} 362]}} The battle around these features, which American soldiers nicknamed the "Death Valley" and "Purple Heart Ridge",{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/314 314]}} began to bend the line of the American advance into a horseshoe,{{sfn|McManus|2021|p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA362|plainurl=yes}} 362]}} creating gaps in the Marine divisions flanks and forcing them to halt.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/179 179]|Hallas|2019|2p=296}}

Frustrated by what he saw as lack of progress by the 27th Division, Holland Smith relieved its commander, Major General Ralph Smith, and temporarily replaced him with another Army officer, Major General Sanderford Jarman.{{sfnm|McManus|2021|1p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA356|plainurl=yes}} 356]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/317 317]|3a1=Smith|3a2=Finch|3y=1949|3pp=[https://archive.org/details/coralbrass0000holl/page/172 172–173]}} The debate over the appropriateness of Holland's Smith action–a Marine general dismissing an Army general–immediately created an inter-service controversy.{{sfn| Shaw|Nalty|Turnbladh|1989|pp=[https://archive.org/details/historyofusmarin03usma/page/317 317–319]}}{{efn|The controversy continues to be debated.{{sfn|Allen|2012|pp=[https://archive.org/details/DTIC_ADA566737/page/1 1–2]}} See {{harvnb|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/191 191–201]}} for a detailed discussion; see {{harvnb|Lacey|2013|pp=157–161}} and {{harvnb|McManus|2021|pp=363–371}} for more recent discussions.}} Despite the replacement of the 27th Infantry Division's commander, it would take six more days for the valley to be captured.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/201 201]}}

File:Rocket-launchers-Saipan2.jpg M–2–4 rocket trucks on Saipan firing a barrage, June 1944|alt= a row of trucks firing rockets. A cloud of dust is behind them.]]

The United States forces had built up substantial firepower to continue their northward drive. On 22 June, P-47s from the Seventh Air Force landed on Aslito Field and immediately began launching ground assault missions.{{sfnm|1a1=Garand|1a2=Strobridge|1y=1989|1p=[https://archive.org/details/historyofusmarin04usma/page/423 423]|2a1=Olson|2a2=Mortensen|2y=1983|2pp=[https://archive.org/details/Vol4ThePacificGuadalcanalToSaipan/page/n763 690–691]}} On the same day, the XXIV Corps Artillery commanded by Brigadier General Arthur M. Harper moved 24 155 mm field guns and 24 155 mm howitzers into place to fire on Japanese positions.{{sfnm|1a1=Crowl|1y=1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/133 133–135]}}

The Americans also used truck-launched rockets{{sfn|M–2–4 Rocket Trucks|2013}} for saturation barrages.{{sfn|Bishop|2014|p=[https://archive.org/details/illustratedencyc0000unse_d5a9/page/186 186]}} Spotters flying in L-4 Grasshoppers helped direct ground artillery,{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/133 133]|2a1=Raines|2y=2000|2p=251}} and Navajo code talkers relayed information about Japanese troop movements.{{sfn|Aaseng|1992|pp=83–[https://archive.org/details/navajocodetalker0000aase/page/85 85]}} In the hills, soldiers relied on personal flamethrowers, particularly in locations where the motorized flamethrowers could not reach.{{sfn|Kleber|Birdsell|1990|p=[https://archive.org/details/CMHPub10-3-nsia/page/n581 563]}} They gradually developed tactics for effectively reducing caves, using a combination of flamethrowers and demolition charges to clear them, or sometimes using demolitions to seal them off.{{sfnm|Hornfischer|2016|1p=[https://archive.org/details/fleetatfloodtide0000horn/page/248 248]|McKinney|1949|2pp=[https://archive.org/details/portable-flamethrower-operations/page/n188 151–152]}}

By 24 June, the American warships that had returned from the Battle of Philippine Sea were once more available to provide fire support.{{sfnm|Hornfischer|2016|1p=[https://archive.org/details/fleetatfloodtide0000horn/page/232 232]|Morison|1981|2pp=[https://archive.org/details/newguineamariana0008samu/page/324 324–325]}}

Ship fire was particularly feared by the Japanese because it could strike from almost any direction.{{sfn|Morison|1981|pp=[https://archive.org/details/newguineamariana0008samu/page/324 324–326]}} Saitō singled out naval gunfire undermining the Japanese' ability to fight successfully against the Americans.{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA332|plainurl=yes}} 332]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/326 326]}}

The ships were also well supplied with star shells, providing illumination that disrupted Japanese night movements and counterattacks.{{sfnm|Hoffman|1950|1pp=[https://archive.org/details/saipanthebeginni00wash/page/90 90–91]|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/502 502]}} This naval support was facilitated by joint assault signal companies that directed both naval and aerial firepower to where it was needed by the ground forces.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/130 130]|Hemler|2021|2pp=136–148|Morison|1981|3pp=[https://archive.org/details/newguineamariana0008samu/page/324 324–325]}}

File:Saipan June 24-crop.png

On 25 June, the 27th Infantry Division was not able to make much headway in their fight for Death Valley, but the 2nd Marine Division to the west gained control of Mount Tapotchau, the key artillery observation posts in Central Saipan.{{sfn|Chapin|1994|p=[https://archive.org/details/BreachingTheMarianas/page/n21 22]}} On the east coast, the 4th Marine Division quickly occupied most of the Kagman peninsula, meeting little organized resistance{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/210 210]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/322 322]}} because the Japanese had evacuated the peninsula.{{sfn|Hallas|2019|p=312}} Between 26 June and 30 June, the 2nd Marine Division and the 27th Infantry Division had made little progress. The second Marines remained south of Garapan and were slowly fighting their way north of Mount Tapotchau. The 4th Marine Division was able to advance up the eastern coast to a line just north of the village of Hashigoru.{{sfn|Shaw|Nalty|Turnbladh|1989|pp=[https://archive.org/details/historyofusmarin03usma/page/326 326–327]}}

About 500 Japanese soldiers broke out of Nafutan point on the night of 26 June. They headed toward Aslito Field, destroying one P-47 and damaging two others.{{sfn|Hallas|2019|p=322}}

They then ran into a unit of Marines who were in reserve and a unit of Marine artillery. Almost all the Japanese soldiers were killed in the ensuing firefight.{{sfn|Chapin|1994|p=[https://archive.org/details/BreachingTheMarianas/page/n22 21]}} The next day, the elements of the 27th Infantry Division that had been fighting at the point moved in to occupy the area, no survivors were found.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/159 159]}}

Igeta's 31st Army Headquarters sent a telegram from the island on 27 June, stating the Japanese would not be able to hold due to the American preponderance in artillery, sea and air power, as well of a lack of equipment and supplies, including food and water.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/212 212–213]}} The lack of water was particularly acute in the limestone caves the Japanese soldiers used for defense.{{sfn|Meehl|2012|p=7}} Igeta reported that some soldiers hadn't had water for three days and were surviving on snails and tree leaves.{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/70 70]}} Japanese communications were so disrupted that at one point during the week, Igeta could only account for 950 of the Japanese soldiers.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/322 322]}}

On June 28, Army Major General George Griner, who had been sent for from Hawaii, took over from command of the 27th Infantry Division. Jarman, whose command had been temporary, returned to his assigned role as garrison commander of the island.{{sfn|Chapin|1994|p=[https://archive.org/details/BreachingTheMarianas/page/n22 23]}} On 30 June, the 27th Infantry Division captured Death Valley and Purple Heart Ridge, and advanced far enough to reestablish contact with the two Marine divisions on their flanks. Saitō's main line of defense in Central Saipan had been breached;{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/231 231–232]}} and the Japanese began their retreat north to their final defensive line.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/331 331]}} To date, American casualties were about 11,000.{{sfn|Chapin|1994|p=[https://archive.org/details/BreachingTheMarianas/page/n25 24]}}

File:Garapan Fire, Saipan, 3 July 1944.jpg on 3 July|alt=two American soldiers running from left to right through a burning village]]

Saitō intended to form a new line in northern Saipan that would be anchored on Tanapag on the west, running southeast to a village called Tarahoho, and through to the east coast.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/221 221]}} He wasn't able to. His army's cohesion was disintegrating: Some of the remaining forces retreated north, others holed up in whatever caves they could find, others put up disorganized resistance where they were.{{sfn|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/500 500]}} During 2–4 July, the 2nd Marine Division took the ruins of Garapan and its harbor.{{sfn|Hallas|2019|p=355}} The 4th Marine Division quickly moved north on the west coast in the face of light resistance.{{sfnm|1a1=Goldberg|1y=2007|1pp=165–169|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/335 335]}}

As Saitō's attempt to form the defense line collapsed,{{sfn|Hallas|2019|p=357}} he eventually moved his final headquarters near Makunsha village on the west coast north of Tanapag.{{sfnm|1a1=Hallas|1y=2019|1p=357|2a1=Hornfischer|2y=2016|2p=266|3a1=Shaw|3a2=Nalty|3a3=Turnbladh|3y=1989|3p=[https://archive.org/details/historyofusmarin03usma/page/339 339]}}

On 4 July, the 27th Infantry Division and 4th Marine Division headed northwest. The 27th division reached the west coast at Flores Point, south of Tanapag,{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/336 336]}} cutting off any Japanese retreating from Garapan.{{sfn|Hornfischer|2016|p=[https://archive.org/details/fleetatfloodtide0000horn_b3y7/page/266 266]}}

The 2nd Marine Division no longer faced organized resistance, and went into reserve. The 27th Infantry Division was to move up the east coast toward Tanapag, and the 4th Marine Division would advance northwest.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/244 244]}} On 5 July, the 27th Infantry Division encountered strong resistance in a narrow canyon on the east coast north of Tanapag that they dubbed "Harikari Gulch", which expanded into a two-day battle.{{sfnm|1a1=Crowl|1y=1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/245 245-246]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2pp=[https://archive.org/details/historyofusmarin03usma/page/337 337-339]|2ps=: see {{harvnb|Small Unit Actions|1991|pp=[https://archive.org/details/SmallUnitActions-nsia/page/n81 69–113]}} for an in-depth description of the fighting.}}

File:Saipan July 7-crop.png assault|upright=1.2]]

The 4th Marine Division continued to make rapid progress north during 4–5 July,{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/247 247–248]}}

and on 6 July, Holland Smith ordered them to head toward the eastern coast near Makunsha to cut off the Japanese forces fighting the 27th Infantry Division,{{sfnm|1a1=Crowl|1y=1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/247 247]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/336 336]}} then the Marines would complete the occupation of the rest of northern Saipan on their own.{{sfn|Heinrichs|Gallicchio|2017||p=[https://archive.org/details/implacablefoeswa0000hein/page/122 122]}}

In the evening, the Marines had taken Mount Petosukara, one of the last mountains before reaching the northern tip of the island,{{sfnm|1a1=Crowl|1y=1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/247 247–248]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/337 337]

}} but the units that turned toward Makunsha encountered too much resistance to reach the eastern coast.{{sfnm|1a1=Hoffman|1y=1950|1p=[https://archive.org/details/saipanthebeginni00wash/page/220 220]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/337 337]}}

Saitō realized he could not create a final defensive line.

His headquarters, which had been under constant artillery attack for days, was now in the range of American machine guns.{{sfnm|Hallas|2019|1p=364|Hornfischer|2016|2p=[https://archive.org/details/fleetatfloodtide0000horn/page/271 271]}} What was left of his command was trapped in a northern corner of the island, almost out of food and water, and slowly being destroyed by overwhelming American firepower.{{sfn|McManus|2021|pp=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA375|plainurl=yes}} 375–376]}} On 6 July, Saitō decided the situation was hopeless and sent out orders for the remainder of his forces to perform gyokusai, one final suicide attack to destroy as many of the enemy as possible.{{sfnm|Hallas|2019|1p=365|Goldberg|2007|2p=273}} He set the attack for the following day to give the troops a chance to concentrate what was left of his forces and put his divisional chief of staff, Colonel Takuji Suzuki,{{sfn|McManus|2021|p=371}} in charge. That night, Saitō ate a last meal and committed seppuku, and Nagumo killed himself around the same time,{{efn|Whether Saitō died with Nagumo or Igeta is unclear. Many sources derive their story from Major Takashi Hirakushi,{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA514|plainurl=yes}} 514, fn44]}} a captured public relations officer.{{sfn|Toland|2003|p=[https://archive.org/details/risingsundecline00john_1/page/490 490]}} who initially claimed to be Major Kiyoshi Yoshida, an intelligence officer who actually died in combat.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/258 258, fn 60]|Hallas|2019|2p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA438|plainurl=yes}} 438]}} (cf.,{{Harvnb|Goldberg|2007|p=173}} who describes the testimony of "Kiyoshi Yoshida"). {{harvnb|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA514|plainurl=yes}} 514, fn44]}} points out that in early accounts, Saitō commits suicide alone (e.g.,see the early account in {{harvnb|Hoffman|1950|loc=[https://archive.org/details/saipanthebeginni00wash/page/282 Appendix IX:The Last Days of General Saitō, pp.283–284]}}), and a different Japanese survivor states that Nagumo committed suicide elsewhere.{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA514|plainurl=yes}} 514, fn44]|Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/337 337]}} {{harvnb|Toland|2003|p=[https://archive.org/details/risingsundecline00john_1/page/511 511]–[https://archive.org/details/risingsundecline00john_1/page/512 512]}}, bases his account, in which Saitō, Nagumo, and Igeta die together on a much later interview with Hirakushi.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA514|plainurl=yes}} 514, fn44]}}}} Takagi stated he would die attacking the enemy.{{sfn|Boyd|Yoshida|2013|p=[{{Google books|id=U2wtWnDBvEgC|pg=PA147|plainurl=yes}} 147]}}

File:2d Marine Division on Tanapag Plain after Gyokusai attack, Saipan July 1944.jpg advancing north on Tanapag Plain on 8 July after the gyokusai attack|alt=tank in mid-left heading down road from left to right. Terrain is flat in foreground, forested cliffs in back ground. Soldiers are walking behind the tank]]

At least 3,000 Japanese combatants participated in the gyokusai attack.{{sfnm|

McManus|2021|1p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA387|plainurl=yes}} 387]|1ps=|

Morison|1981|2p=[https://archive.org/details/newguineamariana0008samu/page/336 336]|2ps=|

Toll|2015|3p=[https://archive.org/details/conqueringtidewa0000toll/page/505 505]|3ps=;

{{Harvnb|Hallas|2019|p=451}} puts then number between 3,000–4,000, and {{Harvnb|Hornfischer|2016|p=[https://archive.org/details/fleetatfloodtide0000horn/page/279 279]}} between 1,500–2,000.}}{{efn|The number of Japanese in the attack is unclear. During the attack, Smith underestimated, stating that only 300–400 were participating.{{sfnm|Gailey|1986|1pp=[https://archive.org/details/howlinmadvsthear0000gail/page/216 216–217]|Hallas|2019|2p=451}} Hirakushi (at that time known as Major Yoshida), who was part of the attack, claimed during his interrogation after being captured that about 1,500 participated.{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/n276 223]}} After the fighting, General Griner of the 27th infantry Division counted 4,311 Japanese bodies in the area of the attack,{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/257 257]}} but it was disputed whether all of them had died in the attack.{{sfn|Hoffman|1950|pp=[https://archive.org/details/saipanthebeginni00wash/page/233 233–234]}} A later commission ordered by Spruance put the number between 1,500–3,000, arguing that many of the bodies were from people who died before the attack. Smith eventually agreed with Spruance's report.{{sfn|Hallas|2019|p=451}}}} They assembled near Makunsha. The force included naval personnel,{{sfn|Gailey|1986|p=[https://archive.org/details/howlinmadvsthear0000gail/page/209 209]}} support troops, civilians,{{sfnm|Hornfischer|2016|1p=[https://archive.org/details/fleetatfloodtide0000horn/page/281 281]|McManus|2021|2p=381}} and the walking wounded.{{sfnm|1a1=Shaw|1a2=Nalty|1a3=Turnbladh|1y=1989|1p=[https://archive.org/details/historyofusmarin03usma/page/340 340]|2a1=Toll|2y=2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/505 505]}} It included three tanks,{{sfn|Hoffman|1950|pp=[https://archive.org/details/saipanthebeginni00wash/page/224 224–225]}} supporting mortars, and machine guns,{{sfn|McManus|2021|p=378}} but some troops were only armed with sticks with bayonets, knives, or grenades tied to poles.{{sfn|Gailey|1986|p=[https://archive.org/details/howlinmadvsthear0000gail/page/209 209]}} It would be the largest gyokusai attack of the Pacific War.{{sfn|Heinrichs|Gallicchio|2017|p=[https://archive.org/details/implacablefoeswa0000hein/page/122 122]}}

At around 04:00, Suzuki's force advanced south along the western coastal area,{{sfn|Gailey|1986|p=[https://archive.org/details/howlinmadvsthear0000gail/page/208 208]}} called the Tanapag plain,{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/340 340]}}

toward where his reconnaissance patrols had found a weak spot in the American line near Tanapag village:{{sfnm|Hallas|2019|1p=381|Hornfischer|2016|2p=[https://archive.org/details/fleetatfloodtide0000horn/page/281 281]|McManus|2021|3p=381}} two battalions of the 105 Infantry Regiment of the 27th Infantry Division were isolated from the other American forces.{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/n276 223]}} The main force struck the two battalions at about 04:45, overrunning both. The two battalions suffered about 900 casualties, which was 80% of their effective force.{{sfnm|Goldberg|2007|1p=182|McManus|2021|2p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA387|plainurl=yes}} 387]}} The charge continued toward Tanapag village, overrunning two batteries of Marine artillery, but was halted in the late morning{{Sfnm|1a1=Shaw|1a2=Nalty|1a3=Turnbladh|1y=1989|1p=[https://archive.org/details/historyofusmarin03usma/page/342 342]|2a1=Toll|2y=2015|2p=[https://archive.org/details/conqueringtidewa0000toll/page/506 506]}} by a hastily formed American line around the village.{{sfnm|Crowl|1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/259 259–260]|Hallas|2019|2p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA104|plainurl=yes}} 104]}} The fighting continued throughout the day, as American soldiers struggled against scattered elements of the gyokusai attack and recaptured lost ground.{{sfnm|1a1=McManus|1y=2021|1p=[{{Google Books|id=7aFHEAAAQBAJ|pg=PA387|plainurl=yes}} 387]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2p=[https://archive.org/details/historyofusmarin03usma/page/342 342]}}

On 8 July, most of the 27th Infantry Division, which had suffered high losses in the gyokusai attack, was placed into reserve. The 2nd Marine Division advanced up the Tanapag plain, looking for Japanese stragglers.{{sfnm|1a1=Crowl|1y=1993|1pp=[https://archive.org/details/CampaignInTheMarianas/page/263 263–264]|2a1=Shaw|2a2=Nalty|2a3=Turnbladh|2y=1989|2pp=[https://archive.org/details/historyofusmarin03usma/page/342 342–343]}} The 4th Marine Division reached the Western coast north of Makunsha and headed toward Marpi point, near the island's northern-most tip.{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/264 264]}} As they advanced, they saw hundreds of Japanese civilians die on inland and coastal cliffs.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/345 345]}} Some threw themselves off, others were thrown or pushed off.{{sfn|Astroth|2019|p=85}} By the evening of 9 July, the 4th Marine Division had reached the northern end of the Island and Turner declared the island secure.{{sfnm|Crowl|1993|1p=[https://archive.org/details/CampaignInTheMarianas/page/263 263]|Hallas|2019|2p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA427|plainurl=yes}} 427]}} On the second day of the battle, he had estimated that Saipan would be captured in a week;{{sfn|Morison|1981|p=[https://archive.org/details/newguineamariana0008samu/page/202 202]}} it had taken 24 days.{{sfn|Forrestel|1966|p=[https://archive.org/details/admiralraymondas0000emme/page/151 151]}} On 11 July, the Americans found General Saitō's body. He was buried on 13 July with full military honors in a coffin draped with the Japanese flag.{{sfn|Hallas|2019|p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PA439|plainurl=yes}} 439]}}

Though the island was declared secured, the fighting and suicides would continue. Clearing the hundreds of scattered Japanese soldiers hiding in caves would take many more months,{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/243 243]}} though the responsibilities were handed over to the Army Garrison Force.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/345 345]}} One group of about 50 Japanese men–soldiers and civilians–was led by Captain Sakae Ōba, who survived the last gyokusai charge.{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=458|plainurl=yes}} 458]}} His group evaded capture and conducted guerrilla-style attacks, raiding American camps for supplies.{{sfn|Gilhooly|2011}} Oba's resistance earned him the nickname "the Fox".{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=458|plainurl=yes}} 458]}} His men held out for approximately 16 months before surrendering on 1 December 1945, three months after the official surrender of Japan.{{sfnm|Gilhooly|2011|1p=|Hallas|2019|2p=[{{Google books|id=kg2QDwAAQBAJ|pg=463|plainurl=yes}} 463]}}

File:A member of a Marine patrol on Saipan found this family of Japs hiding in a hillside cave. The mother, four children an - NARA - 532380.jpg talks a woman with children and a dog into leaving a hillside cave on 21 June|alt=Women with children and dog sitting in cave on left facing a marine squatting on the right who is looking at her.]]

Almost the entire Japanese garrison–approximately 30,000 military personnel–were killed in the battle. Eventually 1,700, about half of whom were Korean workers, were taken prisoner.{{sfn|Shaw|Nalty|Turnbladh|1989||p=[https://archive.org/details/historyofusmarin03usma/page/345 345]}} American forces suffered about 16,500 casualties –3,100 killed and 13,000 wounded–{{sfn|Hallas|2019|p=444}} out of 71,000 who were part of the assault force.{{sfn|McManus|2021|p=388}} The casualty rate was over 20%,{{sfnm|1a1=Hallas|1y=2019|1p=444|2a1=Heinrichs|2a2=Gallicchio|2y=2017|2p=[https://archive.org/details/implacablefoeswa0000hein/page/124 124]|3a1=McManus|3y=2021|3p=388}} which was comparable to Tarawa.{{sfn|Hallas|2019|p=444}} It was the Americans' most deadly battle in the Pacific up to that time.{{sfn|Toland|2003|p=[https://archive.org/details/risingsundecline00john_1/page/519 519]}}

Approximately 40% of the civilians on Saipan were killed. Around 14,000 survived and were interned,{{sfnm|Astroth|2019|1p=165|American Memorial Park|2021|2p=}} but an estimated 8,000{{sfn|American Memorial Park|2021}} to 10,000{{sfn|Astroth|2019|p=166}} died during the fighting or shortly afterwards. Many civilians died from the bombing, shelling and cross-fire.{{sfn|Trefalt|2018|pp=255–256}} Others died because they hid in caves and shelters that were indistinguishable from Japanese combat positions, which the Marines typically destroyed with explosives, grenades and flamethrowers.{{sfnm|Astroth|2019|1pp=143–144|Hughes|2001|2pp=110–111}} Though many civilians were able to surrender early in the battle, surrender became more difficult as the battle moved into the northern mountains. Obscuring terrain made it hard to distinguish combatants and surrendering civilians, who risked being killed by both sides. Many refused to surrender because they believed rumors that the Japanese fleet was coming to rescue them.{{sfnm|Sheeks|1945|1pp=110–111|Trefalt|2018|2p=259}} Others refused because of the fear spread by Japanese propaganda that Americans would rape, torture and kill them; others were coerced.{{sfn|Astroth|2019|p=105}} Around 1,000 civilians committed suicide during the final days of the battle,{{sfn|Astroth|2019|p=167}} some after 9 July when the island had been declared secure.{{sfn|Astroth|2019|p=96}} Many died by throwing themselves off cliffs at places that would become known as "Suicide Cliff" and "Banzai Cliff".{{sfn|Astroth|2019|p= [{{Google books|id=znOPDwAAQBAJ|pg=PA25|plainurl=yes}} 25]}}

File:Draper (1944) An LVT Comes Ashore, Saipan.jpg Comes Ashore, Saipan, a 1944 oil painting by William Franklin Draper.(Navy Art Collection, Naval History and Heritage Command)|upright=1.2|alt=tracked landing vehicle on right, tree on left, in center and right are shirtless soldiers waiting around, ships are in the background.]]

The American forces brought their supplies with the invasion fleet,{{sfn|O'Hara|2019|loc=Geography and Weather}} carrying over one ton of supplies per soldier:{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/256 256]}} 32 days of rations, 30 days of medical supplies, 20 days of maintenance supplies, seven days of ammunition for ground weapons, and ten days of anti-aircraft ammunition.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/242 242]}} Mobile reserves{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/24 24]}} and an ammunition resupply train,{{sfn|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/502 502]}} as well as regular resupply shipments came from depots at Eniwetok,{{sfn|Coakley|Leighton|1987|p=[https://archive.org/details/GlobalLogisticsAndStrategy1943-1945/page/n475 450]}} which was {{convert|1017|mi|km|abbr=on}} from Saipan.{{sfn|O'Hara|2019|loc=Geography and Weather}}

During the early days of the invasion, LVTs dumped boxes of rations, water and ammunition on the beaches.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/276 276]}} Heavy swells on the first days forced many of the supplies to be loaded on only one beach,{{sfn|O'Hara|2019|loc=Geography and Weather}} and LVTs were required to get over reefs that restricted access.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/124 124]}} Constant Japanese mortar and artillery fire interfered with organizing these supplies for the first three days. Unloading became haphazard, and some units had difficulty finding their equipment.{{sfn|Dod|1987|p=[https://archive.org/details/CMHPub10-6-nsia/page/n513 497]}} The withdrawal of the transports for five days during the Battle of Philippine Sea also slowed down the delivery of supplies.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/123 123–124]}}

The 27th Infantry Division particularly suffered from this initial disorganization. No plans had been made for its landing and it did not have an assigned unloading area. Its equipment was mixed up with the Marine divisions and its artillery ammunition was misplaced.{{sfn|Shaw|Nalty|Turnbladh|1989|p=[https://archive.org/details/historyofusmarin03usma/page/348 348–350]}} Because it arrived on Saipan after the Marine divisions, the 27th Infantry Division had less time to unload its supplies before the transports temporarily headed east on 18 June. Initially, the division only had enough infantry ammunition for four days. Food and artillery ammunition had to be borrowed from the Marines, and water had to be supplemented from cisterns captured at Aslito Field.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/124 124–127]}}

Later in the campaign, mortar ammunition ran low as planners had underestimated how frequently they would be used, and there were shortages of motorized transportation, which was used for getting supplies from the beach to the frontline. Naval ships ran low on star shells due to their high demand, and their use had to be rationed. Despite these issues, the overall supply situation during the battle was good: the Americans had an abundance of materiel.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/128 128–130]}}

The Japanese troops had no chance of reinforcement.{{sfn|O'Hara|2019|loc=Threats}} From January to June, the Japanese had tried to ship men and supplies to Saipan,{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/58 58–60]}} but many ships around the island were torpedoed by American submarines. The Japanese government reported that one ship out of three sent to the Marianas were sunk and another was damaged.{{sfn|Hoffman|1950|p=[https://archive.org/details/saipanthebeginni00wash/page/9 9]}} Though many of the men survived, almost all the materiel was lost.{{sfn|Crowl|1993|pp=[https://archive.org/details/CampaignInTheMarianas/page/58 58–60]}} For example, on 25 May two freighters from Saipan to Palau were torpedoed, destroying 2,956 tons of food, 5,300 cans of aviation fuel, 2,500 cubic meters of ammunition, and 500 tons of cement.{{sfn|Wetzler|2020|p=[{{Google books|id=P6rFDwAAQBAJ|pg=PA137|plainurl=yes}} 137]}}

At the beginning of the battle, the Americans had six times the tanks, five times the artillery, three times as many small arms, and two times as many machine guns available as the Japanese. The Americans also had much more ammunition.{{sfn|Wetzler|2020|p= 134}} The U. S. Navy fired 11,000 tons of shells during the battle, including over 14,000 rounds of 5-inch ammunition.{{sfn|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/502 502]}} Unlike the Americans, who could replenish their supplies, the Japanese could not. They had to fight with what was available when the invasion started, and when it ran out they were expected to die honorably, resisting until the end.{{sfn|Wetzler|2020|p=[{{Google books|id=P6rFDwAAQBAJ|pg=PA143|plainurl=yes}} 143]}}

The invasion of Saipan and the invasion of France in Operation Overlord demonstrated the dominance of American industrial power. Both were massive amphibious invasions–the two largest up to that time–and they were launched almost simultaneously on separate halves of the globe.{{sfn|Toll|2015|p=[https://archive.org/details/conqueringtidewa0000toll/page/457 457]}} Together, they were the greatest deployment of military resources by the United States at one time.{{sfn|O'Hara|2019}} Because the Battle of Saipan began just over a week after the 6 June landings for Overlord, its importance has often been overlooked, but just as Overlord was a major step in contributing to the fall of the Third Reich, Saipan marked a major step in the collapse of the Empire of Japan.{{sfn|Hallion|1995|p=45}}

File:Isely Field with B-29s in mid 1945.jpg, filled with B-29 bombers, mid-1945|left|alt=Aerial view of over 120 bombers parked on large airfield running from lower left to upper right.]]

The availability of Saipan as an American airbase, along with the airbases already established in Chengdu, opened a new phase in the Pacific War, in which strategic bombing would play a major role.

The 15 June invasion of the island had been synchronized with bombing of the Yawata Steel Works by B-29s in China. It was the first bombing of the Japan home islands by B-29s, signaling the beginning of a campaign that could strike deep into Japan's Absolute National Defense Zone.{{sfn|Craven|Cate|1983|p=[https://archive.org/details/Vol5ThePacificMatterhornToNagasaki/page/n39 3–4]}}

The Army Air Force was confident that strategic bombing could destroy Japan's [[Military production during World War II|

military production]] and that the Marianas provided excellent airbases for doing so because they were {{convert|1200|mi|km|abbr=on}} miles from the Japanese home islands. This put almost all of Japan's industrial cities within striking distance of the B-29 bomber,{{sfnm|1a1=Shaw|1a2=Nalty|1a3=Turnbladh|1y=1989|1p=[https://archive.org/details/CentralPacificDrive-nsia/page/n237 233]|2a1=Toll|2y=2015|2p= [https://archive.org/details/conqueringtidewa0000toll/page/307 307]}} and the airbases were easy to defend and supply.{{sfn|Miller|1991|p=[https://archive.org/details/warplanorangeuss0000mill/page/344 344]}}

Saipan was the first island to base the B-29s. Construction of an aerodrome for B-29s began on Isely Field – the renamed Aslito Field – on 24 June,{{sfn|Crowl|1993|p=[https://archive.org/details/CampaignInTheMarianas/page/443 443]}} before the island was declared secure. The first runway was complete by 19 October and the second by 15 December.{{sfn|Craven|Cate|1983|p=[https://archive.org/details/Vol5ThePacificMatterhornToNagasaki/page/n574 517]}} The 73rd Bombardment Wing began arriving on 12 October. On 24 November,{{sfn|Craven|Cate|1983|p=[https://archive.org/details/Vol5ThePacificMatterhornToNagasaki/page/n15 xvii]}} 111 B-29s set out for Tokyo in the first strategic bombing mission against Japan from the Marianas.{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=PA458|plainurl=yes}} 458]}}

The casualties on Saipan were used by American planners to predict American losses in future engagements.{{sfn|Hallas|2019|p=[{{Google books|id=kg2QDwAAQBAJ|pg=PR6|plainurl=yes}} vi]}} This "Saipan ratio" – one killed American and several wounded for every seven Japanese soldiers killed – became one of the justifications for American planners to increase conscription, projecting an increased need for replacements in the war on Japan.{{sfn|Giangreco|2003|pp=99–100}} Its prediction of high casualties was part of the reason that the Joint Chiefs of Staff did not approve an invasion of Taiwan.{{sfn|Craven|Cate|1983|p=[https://archive.org/details/Vol5ThePacificMatterhornToNagasaki/page/n439 390]}} The Saipan ratio guided the initial estimate that the invasion of Japan would cost up to 2,000,000 American casualties,{{sfn|Giangreco|2003|p=104}} including 500,000 killed.{{sfnm|Giangreco|2003|1pp=99–100|Hallas|2019|2p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PR6|plainurl=yes}} vi]}} Though these estimates would be revised downward later, they would still influence politicians' thinking about the war well into 1945.{{sfn|Dower|2010|pp=[https://archive.org/details/culturesofwarpea0000dowe/page/216 216–217]|ps=; also see discussion in {{harvnb|Giangreco|2003|pp=127–130}}}}

File:Civilian with baby Saipan (cropped).jpg

Saipan's loss had a greater impact in Japan than any of its previous defeats.{{sfn|Morison|1981|pp=[https://archive.org/details/newguineamariana0008samu/page/339 339–340]}}

The Emperor of Japan, Hirohito, recognized that American control of the island would result in Tokyo being bombed. After the Japanese defeat at the Battle of Philippine Sea, he demanded that the Japanese General Staff plan another naval attack to prevent its fall.{{sfn|Bix|2000|p=[https://archive.org/details/hirohitomakingo00bixh/page/476 476]}} Hirohito only accepted Saipan's eventual fall on 25 June 1944 when his advisors told him all was lost.{{sfn|Toll|2015|pp=[https://archive.org/details/conqueringtidewa0000toll/page/530 530]–[https://archive.org/details/conqueringtidewa0000toll/page/531 531]}} The defeat brought the collapse of Hideki Tōjō's government. Disappointed with the progress of the war, Hirohito withdrew his support for Tōjō, who resigned as prime minister of Japan on 18 July.{{sfn|Bix|2000|p= [https://archive.org/details/hirohitomakingo00bixh/page/478 478]}} He was replaced by former General Kuniaki Koiso,{{sfn|Sullivan|1995|p=35}} who was a less capable leader.{{sfn|Frank|1999|pp=[https://archive.org/details/downfallendofimp00fran/page/90 90–91]}}

Saipan's fall led the Japanese government's war reporting to admit for the first time that the war was going poorly. In July, Imperial General Headquarters published a statement providing a summary of the battle and the loss of the island, and the government allowed a translation of a Time magazine article, which included the civilian suicides on the last days of the battle, to be published in The Asahi Shimbun, Japan's largest newspaper, while the battle was in progress.{{sfnm|Hoyt|2001|1pp=[https://archive.org/details/japanswargreatpa0000hoyt/page/351 351–352]|1ps=|Kort|2007|2p=61|ps=: see complete statement of the Imperial Japanese Headquarters in {{Harvnb|Hoyt|2001|loc=[https://archive.org/details/japanswargreatpa0000hoyt/page/430 Appendix A, pp 426–430]}}}} Before the battle had ended, the Japanese government issued the "Outline for the Evacuation of Schoolchildren" in June, anticipating the bombing of Japan's cities.{{sfn|Plung|2021|loc=§11}} This evacuation, the only compulsory one enacted during the war,{{sfn|Plung|2021|loc=§11}} separated more than 350,000 third-through sixth-graders who lived in major cities from their families and sent them into the countryside.{{sfn|Havens|1978|pp=[https://archive.org/details/havensvalleyofda00trhh/page/162 162–163]}}

The capture of Saipan pierced the Absolute National Defense Zone,{{sfn|Tanaka|2023|loc=Widening the War into the Asia-Pacific Theatre of World War II, The Third Stage §7}} forcing the Japanese leadership to reconsider the outcomes they could expect for the war.{{sfnm|Hallas|2019|1p=[{{Google Books|id=kg2QDwAAQBAJ|pg=PR6|plainurl=yes}} vi]|Kase|1950|2pp=[https://archive.org/details/journeytomissour0000tosh/page/73 73–78]}}

In July, the Chief of the War Guidance department of Imperial General Headquarters, Colonel Sei Matsutani,{{sfn|Kawamura|2015|p= [{{Google books|id=QianCgAAQBAJ|pg=PA114|plainurl=yes}} 114]}} drafted a report stating that the conquest of Saipan destroyed all hope of winning the war.{{sfnm|Irokawa|1995|1p=[https://archive.org/details/ageofhirohitoins00irok/page/92 92]|Kawamura|2015|2pp= [{{Google books|id=QianCgAAQBAJ|pg=PA129|plainurl=yes}} 129]–[{{Google books|id=QianCgAAQBAJ|pg=PA130|plainurl=yes}} 130]}} After the war, many Japanese military and political leaders stated that Saipan was a turning point as well.{{sfn|Mission Accomplished|1946|p=[{{Google books|id=ge5mAAAAMAAJ|pg=PA18|plainurl=yes}} 18]|ps=: see supporting quotes by several leaders on pp. [{{Google books|id=ge5mAAAAMAAJ|pg=PA18|plainurl=yes}} 18–19]}} For example, Vice Admiral Shigeyoshi Miwa stated "Our war was lost with the loss of Saipan,"{{sfn|Shaw|Nalty|Turnbladh|1989|p= [https://archive.org/details/historyofusmarin03usma/page/346 346]|ps=: see quote in {{harvnb|Interrogations of Japanese Officials|1946|p=297}}}} and Fleet Admiral Osami Nagano acknowledged the battle's importance, saying "When we lost Saipan, Hell is on us."{{sfnm|Hallas|2019|1p= 440|Hoffman|1950|2p=[https://archive.org/details/saipanthebeginni00wash/page/260 260]|ps=: see quote in {{harvnb|Interrogations of Japanese Officials| 1946|p=355}}}}

Suicide Cliff and Banzai Cliff, along with surviving isolated Japanese fortifications, are recognized as historic sites on the U.S. National Register of Historic Places. The cliffs are part of the National Historic Landmark District Landing Beaches; Aslito/Isley Field; & Marpi Point, Saipan Island, which includes the American landing beaches, the B-29 runways of Isley Field, and the surviving Japanese infrastructure of the Aslito and Marpi Point airfields.{{sfn|National Historic Locations Application|2015}} The Maritime Heritage Trail has a series of dive sites with submerged ships, planes and tanks from the battle.{{sfn|McKinnon|2011}} The American Memorial Park commemorates the American and Mariana people who died during the Mariana Islands campaign,{{sfn|National Park Foundation|2022}} and The Central Pacific War Memorial Monument is dedicated to the memory of the Japanese soldiers and civilians who died.{{Sfn|Saipan Memorial Service|2016}}

{{Gallery|mode=packed|align=center|width=220|File:American Memorial Park3.jpg|American Memorial Park|alt1=Perspective photograph of Park, which rises on wide stairs ending with a court and a flag circle of five flags|File:Banzai Cliff Cenotaphs2.JPG|Cenotaphs near Banzai Cliff|alt2=cenotaphs on grass lined up from lower left to mid right side with ocean in background.|File:Banzai Cliff in Saipan.JPG|Banzai Cliff, with cenotaphs visible in the upper left corner|alt3=coastal cliff on left, ocean on right, cenotaphs in upper left corner}}

{{Notelist}}

{{Reflist}}

{{see also|Bibliography of the Battle of Saipan}}

{{Refbegin|30em}}

• {{cite book|last=Aaseng|first=Nathan|year=1992|title=Navajo Code Talkers|publisher=Walker|isbn=0802776272|oclc=49275457}}
• {{cite book|last=Astroth|first=Alexander|year=2019|title=Mass Suicides on Saipan and Tinian, 1944: An Examination of the Civilian Deaths in Historical Context|publisher=McFarland|isbn=9781476674568|oclc=1049791315}}
• {{cite book|editor-last=Bishop|editor-first=Chris|year=2014|title=The Illustrated Encyclopedia of Weapons of World War II:A Comprehensives Guide to the Weapons Systems. Including Tanks, Small Arms, Warplanes, Artillery, Ships, and Submarines|oclc=1310751361|isbn=9781782743880|publisher=Metro Books}}
• {{cite book|last=Bix|first=Herbert P.|author-link=Herbert P. Bix|title=Hirohito and the Making of Modern Japan|date=2000|publisher=Harper Collins|isbn=9780060193140|oclc=43031388}}
• {{cite book|last1=Boyd|first1=Carl|last2=Yoshida|first2=Akihiko Yoshida|year=2013|title=Japanese Submarine Force and World War II|publisher=Naval Institute Press|oclc=1301788691|isbn=9781612512068}}
• {{Cite book|last=Chapin|first=John C.|title=The Battle for Saipan|publisher=United States Marine Corps Historical Division|year=1994|id=PCN 19000312300|url=https://archive.org/details/BreachingTheMarianas}}
• {{cite book|last1=Coakley|first1=Robert W.|last2=Leighton|first2=Robert M|year=1987|orig-year=1968|title=Global Logistics and Strategy|series=United States Army in world War II|publisher=Center of Military History|url=https://archive.org/details/GlobalLogisticsAndStrategy1943-1945|oclc=1048609737}}
• {{cite book|editor1-last=Craven|editor1-first=Wesley F.|editor2-last=Cate|editor2-first=James L.|editor2-link=James L. Cate|year=1983|orig-year=1953|title=The Pacific: Matterhorn to Nagasaki, June 1944 to August 1945|series=The Army Air Forces in World War II|publisher=Office of Air Force History|volume = 5|isbn=9780912799032|oclc=9828710|url=https://archive.org/details/Vol5ThePacificMatterhornToNagasaki}}
• {{cite book|last=Cressman|first=Robert J.|year=2000|title=The Official Chronology Of The U.S. Navy In World War II|publisher=Naval Historical Center|url=https://archive.org/details/TheOfficialChronologyOfTheUSNavyInWorldWarII-nsia|isbn=9781682471548|oclc=607386638}}
• {{cite book|last=Crowl|first=Philip A. |title=Campaign in the Marianas|year=1993|orig-year=1960|series=United States Army in World War II, The War in the Pacific|publisher=Center of Military History, United States Army|oclc=1049152860|url=https://archive.org/details/CampaignInTheMarianas}}
• {{cite book|last=Dod|first=Karl C.|year=1987|orig-year=1966|title=The Corps of Engineers: The War Against Japan|publisher=Center of Military History, United States Army|oclc=17765223|series=United States Army in World War II}}
• {{cite book |last=Dower |first=John W. |author-link=John W. Dower|title=Cultures of War: Pearl Harbor, Hiroshima, 9–11, Iraq |location=New York |publisher=Norton New Press |date=2010 |isbn=978-0-393-06150-5|oclc=601094136}}
• {{cite book|last=Forrestel|first=Emmet P.|year=1966|title=Admiral Raymond A. Spruance, USN: A Study in Command|publisher=U. S. Government Printing Office|oclc=396044|url={{Google books|id=_5KwAAAAIAAJ|plainurl=yes}}}}
• {{cite book |last=Frank |first=Richard B. |title=Downfall: The End of the Imperial Japanese Empire |publisher=Random House |year=1999 |isbn=9780679414247|oclc=40783799}}
• {{Cite book |last= Gailey | first = Harry A. | year = 1986 | title = Howlin' Mad vs. the Army: Conflict in Command, Saipan 1944 | publisher = Presidio Press | isbn = 0-89141-242-5|oclc=13124368 }}
• {{cite book|last1=Garand|first1=George W.|last2=Strobridge|first2=Truman R.|year=1989|orig-year=1971 |title=Western Pacific Operations|volume=4|chapter= Part V. Marine Aviation in the Western Pacific: 2. Marine Aviation in the Marianas, Carolines, and at Iwo Jima|series=History of U.S. Marine Corps Operations in World War II|url=https://archive.org/details/historyofusmarin04usma|publisher=Historical Branch, G–3 Division, Headquarters, U. S. Marine Corps|pages=422–442|oclc=1046596050}}
• {{cite book|last=Goldberg|first=Harold J.|year=2007|title=D-Day in the Pacific: The Battle of Saipan|publisher=Indiana University Press, 2007|isbn=978-0-253-34869-2|oclc=73742593}}
• {{cite book|last=Hallas|first=James H.|year =2019|title=Saipan: The Battle That Doomed Japan in World War II|publisher=Stackpole|isbn=9780811768436|oclc=1052877312}}
• {{cite book|last=Harmsen|first=Peter|year=2021|title=War in the Far East: Asian Armageddon 1944–1945|volume=3|publisher=Casemate|isbn=9781612006277|oclc=1202754434}}
• {{cite book|last=Havens|first=Thomas R.|author-link=Thomas Havens|year=1978|title=Valley of Darkness: The Japanese People and World War Two|publisher=Norton|oclc=1035086075|isbn=9780393056563}}
• {{cite book|last1=Heinrichs|first1= Waldo H.|last2=Gallicchio|first2=Marc|year=2017|title=Implacable Foes: War in the Pacific, 1944–1945|chapter=The Marianas Campaign, June–August 1944|publisher=Oxford University Press|isbn=9780190616755|oclc=962442415}}
• {{Cite book|last=Hiroyuki|first=Shindo|editor1-last=Reichherzer|editor1-first=Frank|editor2-last=Ishizu|editor2-first=Tomoyuki|year=2022|title=NIDS-ZMSBw Joint Research Project 2019–2021: Sharing Experiences in the 20th Century–Joint Research on Military History|chapter=From the Offensive to the Defensive: Japanese strategy During the Pacific War, 1942–1944|chapter-url=https://www.nids.mod.go.jp/english/publication/joint_research/series19/pdf/chapter08.pdf|archive-url=https://web.archive.org/web/20220615004727/https://www.nids.mod.go.jp/english/publication/joint_research/series19/pdf/chapter08.pdf|archive-date=15 June 2022|publisher=National Institute for Defense Studies, Japan|isbn=9784864821049|oclc=1407570510|series=NIDS Joint Research Series |id=No. 19}}
• {{cite book|last=Hoffman|first=Carl W.|year =1950|title=Saipan: The Beginning of the End|publisher=Historical Branch, United States Marine Corps| author-link=Carl W. Hoffman|url={{Google books|id=HvBmAAAAMAAJ|plainurl=yes}}|oclc=564000243}}
• {{cite book|last=Hopkins|first=William B.|author-link=William B. Hopkins|year=2008|title=The Pacific War: The Strategy, Politics, and Players That Won the War|publisher=Zenith|isbn=9780760334355 |oclc=1311044045}}
• {{cite book|last=Hornfischer|first=James D.|author-link=James D. Hornfischer |title=The Fleet at Flood Tide: The U.S. at Total War in the Pacific, 1944–1945|year=2016|publisher=Random House Publishing Group| isbn=978-0345548726|oclc=1016508640}}
• {{cite book|last=Hoyt|first=Edwin P.|author-link=Edwin Palmer Hoyt|year=2001|orig-year=1986|title=Japan's War: The Great Pacific Conflict|isbn=9780815411185|oclc=45835486}}
• {{cite book|last=Irokawa|first=Daikichi|author-link=Daikichi Irokawa|year=1995|title=The Age of Hirohito: In Search of Modern Japan|publisher=Free Press|oclc=1024165290|isbn=9780029156650}}
• {{cite book|last=Kawamura|first=Noriko|author-link=Noriko Kawamura|year=2015|title=Emperor Hirohito and the Pacific War|publisher=University of Washington Press|isbn=9780295806310|oclc=922925863}}
• {{cite book|last1=Kleber|first1=Brooks E.|last2=Birdsell|first2=Dale|year=1990|orig-year=1966|title=The Chemical Warfare Service: Chemicals in Combat|series=United States Army in World War II: The Technical Services|publisher=Center of Military History, United States Army|url=https://archive.org/details/CMHPub10-3-nsia|oclc=35176837}}
• {{cite book|last=Kort|first=Michael|author-link=Michael Kort|year=2007|title=Columbia Guide to Hiroshima and the Bomb|publisher=Columbia University|chapter=The Japanese Government, Ketsu-Go, and Potsdam|pages=58–66|doi=10.7312/kort13016 |jstor=10.7312/kort13016.9|isbn=9780231130165|oclc=71286652}}
• {{cite book|last=Lacey|first=Sharon T.|year=2013|title=Pacific Blitzkrieg: World War II in the Central Pacific|publisher=University of North Texas Press|isbn=9781574415254|oclc=861200312}}
• {{cite book|last=Matloff|first=Maurice|author-link=Maurice Matloff|year=1994|orig-year=1959|title=Strategic Planning for Coalition Warfare 1943–1944|series=United States Army in World War II: The War Department|publisher=Center of Military History, United States Army|oclc=1048613899|url=https://archive.org/details/StrategicPlanningForCoalitionWarfare1943-1944}}
• {{cite book|last=McManus|first=John C.|author-link=John C. McManus |year=2021|title=Island Infernos|publisher=Penguin|isbn=9780451475060|oclc=1260166257}}
• {{cite book|last=Meehl|first=Gerald A.|year=2012|title=One Marine's War: A Combat Interpreter's Quest for Humanity in the Pacific|publisher=Naval Institute Press|isbn= 9781612510927|oclc=811408315}}
• {{cite book|last=Miller|first=Edward S.|year=1991|title=War Plan Orange: The U. S. Strategy to Defeat Japan, 1897–1945|publisher=Naval Institute Press|isbn=9780870217593|oclc=23463775}}
• {{cite book|last=Millett|first=Allan R.|author-link=Allan R. Millett|year=1980|title=Semper Fidelis: The History of the United States Marine Corps|publisher=Macmillan|isbn=9780029215906|oclc=1280706539}}
• {{cite book |last=Morison |first=Samuel Eliot |title=New Guinea and the Marianas, March 1944–August 1944 |date=1981|orig-date=1953 |volume=8 |series=History of United States Naval Operations in World War II |author-link=Samuel Eliot Morison|publisher=Little Brown|isbn=9780316583084|oclc=10926173}}
• {{Cite book|last=Murfett|first=Malcolm H.|year=2008|title=Naval Warfare 1919–45: An Operational History of the Volatile War at Sea|publisher=Francis & Taylor|isbn=9781134048137|doi=10.4324/9780203889985|oclc=900424339}}
• {{cite book|last1=Olson|first1=James C.|last2=Mortensen|first2=Bernhardt L.|editor-last1=Craven|editor-first1=Wesley F.|editor-last2=Cate|editor-first2=James L.|author1-link =James C. Olson|year=1983|orig-year=1950|title=The Pacific: Guadalcanal to Saipan, August 1942 to July 1944|series=The Army Air Forces in World War II|volume=4|chapter=The Marianas|oclc=9828710|isbn=

9780912799032|pages=671–696|chapter-url=https://archive.org/details/Vol4ThePacificGuadalcanalToSaipan/page/n741}}

• {{cite book |last=Raines |first=Edgar F. Jr. |title=Eyes of Artillery: The Origins of Modern U.S. Army Aviation In World War II|series=Army Historical Series |id=CMH Pub 70-31 |publisher=Center of Military History, United States Army|year=2000|url=https://history.army.mil/html/books/070/70-31-1/CMH_Pub_70-31-1.pdf|archive-url=https://web.archive.org/web/20150920132725/https://history.army.mil/html/books/070/70-31-1/CMH_Pub_70-31-1.pdf|archive-date=20 September 2015|oclc=606557132}}
• {{cite book|last1=Shaw|first1=Henry I. Jr.|first2=Bernard C.|last2=Nalty|first3=Edwin T.|last3=Turnbladh|year=1989|orig-year=1966 |title=Central Pacific Drive|volume=3|series=History of U.S. Marine Corps Operations in World War II|url=https://archive.org/details/historyofusmarin03usma|publisher=Historical Branch, G–3 Division, Headquarters, U. S. Marine Corps|isbn=9780898391947|oclc=927428034}}
• {{cite book|last=Smith|first=Douglas V.|year=2006|title=Carrier Battles: Command Decision in Harm's Way|publisher=Naval Institute Press|oclc=1301788691|isbn=1591147948}}
• {{cite book|last=Smith|first=Robert R.|year=1996|orig-year=1953|title=The Approach to the Philippines|series=United States Army in World War II: The War in the Pacific|publisher=Center of Military History, United States Army|oclc=35911873|url=https://archive.org/details/TheApproachToThePhilippines-nsia}}
• {{Cite book|last=Symonds|first=Craig L.|author-link=Craig L. Symonds|year=2022|title=Nimitz at War: Command Leadership from Pearl Harbor to Tokyo Bay|publisher=Oxford University Press|isbn=9780190062361|oclc=1268206579}}
• {{cite book|last=Tanaka|first=Yuki|author-link=Yuki Tanaka (historian)|year=2023|editor-last=Hein|editor-first=Laura E.|series=The New Cambridge History of Japan|title=The Modern Japanese Nation and Empire c. 1868 to the Twenty-First Century|volume=III|chapter=Asia-Pacific War|pages=138–167 |type=eBook|publisher=Cambridge University Press|doi=10.1017/9781108164535.007|isbn=9781108164535|oclc=1382587192}}
• {{cite book|last= Toland|first= John|author-link=John Toland (author)|title=The Rising Sun: The Decline and Fall of the Japanese Empire 1936–1945|publisher=Random House|year=2003|orig-year= 1970|isbn=9780812968583|oclc=52441692}}
• {{cite book|last=Toll|first=Ian W.|author-link=Ian W. Toll|year=2015|title=The Conquering Tide: War in the Pacific Islands, 1942–1944|publisher=W. W. Norton|isbn=978-0393080643|oclc=902661305}}
• {{cite book|author=United States War Department Historical Division|year=1991| orig-year=1946|title=Small Unit Actions – France: 2d Ranger Battalion at Pointe du Hoe; Saipan: 27th Division on Tanapag Plain; Italy: 351st Infantry at Santa Maria Infante; France: 4th Armored Division at Singling|chapter=The Fight on Tanapag Plain: 27th Division, 6 July 1944|publisher=War Department, Historical Division|pages=69–113|chapter-url=https://archive.org/details/SmallUnitActions-nsia/page/n81|oclc=519761473|ref={{SfnRef|Small Unit Actions|1991}}}}
• {{cite book|last=Vlahos|first=Michael|year=1980|title=The Blue Sword: The Naval War College and the American Mission 1919–1941|publisher=Naval War College|oclc=7577592|url=https://archive.org/details/blueswordnavalwa00vlah}}
• {{cite book|last=Wetzler|first=Peter|year=2020|title=Imperial Japan and Defeat in the Second World War: The Collapse of an Empire|publisher= Bloomsbury Academic|isbn=9781350120815|oclc=1113926749}}
• {{cite book|editor-last=Willoughby|editor-first=Charles A.|editor-link=Charles A. Willoughby|year=1994|orig-year=1950|title=Reports of General MacArthur: Japanese Operations in the Southwest Pacific Area|volume=II, Part I|url=https://archive.org/details/ReportsOfGeneralMacarthurJapaneseOperations-nsia|publisher=U. S. Government Printing Office|oclc=1054369044}}
• {{cite book|last=Winton|first=John|author-link=John Winton|year=1993|title=Ultra in the Pacific: How Breaking Japanese Codes and Ciphers Affected Naval Operations Against Japan 1941–1945|publisher=Naval Institute Press|isbn=9781557508560|oclc=29918990}}
• {{cite book|last=Y'Blood|first=William T.|author-link=William T. Y'Blood|year=1981|title=Red Sun Setting: The Battle of the Philippine Sea|publisher=Naval Institute Press|oclc=7178031|isbn=9780870215322}}
• {{cite book|last=Zaloga|first=Steven J.|author-link=Steven J. Zaloga|year=2012|title= M4 Sherman vs. Type 97 Chi-Ha: The Pacific 1945|publisher=Osprey|oclc=798085213|isbn=9781849086387}}

{{refend}}

{{Refbegin|30em}}

• {{cite report|last=Allen|first=William B.|year=2012|title=Sacked at Saipan|type=Monograph|publisher=School of Advanced Military Studies, United States Army Command an General Staff College|url=https://archive.org/details/DTIC_ADA566737|via=Defense Technical Information Center}}
• {{cite report|last1=Cloud|first1=Preston|author-link=Preston Cloud|last2=Schmidt|first2=Robert G.|last3=Burke|first3=Harold W.|title=Geology of Saipan: Mariana Islands – Part 1. General Geology|year=1956|publisher=United States Geological Survey |url=https://pubs.usgs.gov/pp/0280a/report.pdf|archive-url=https://web.archive.org/web/20170228011005/https://pubs.usgs.gov/pp/0280a/report.pdf|archive-date= 28 February 2017|type=Report}}
• {{cite report|publisher=US Army Corps of Engineers|date=2022|title=The Commonwealth of the Northern Mariana Islands: Final Post Disaster Watershed Plan|url=https://www.poh.usace.army.mil/Portals/10/docs/Civil%20Works/CNMI%20Watershed/01%20CNMI_FinalReport_July2022.pdf|archive-url=https://web.archive.org/web/20240117041130/https://www.poh.usace.army.mil/Portals/10/docs/Civil%20Works/CNMI%20Watershed/01%20CNMI_FinalReport_July2022.pdff|archive-date=17 January 2024|ref={{SfnRef|USACE|2022|type=Report}}}}
• {{cite journal|last=Giangreco|first=D. M.|author-link=Dennis Giangreco|year=2003|title=A Score of Bloody Okinawas and Iwo Jimas: President Truman and casualty estimates for the invasion of Japan|journal=Pacific Historical Review|volume=72|issue=1|pages=93–132|doi=10.1525/phr.2003.72.1.93 |jstor=10.1525/phr.2003.72.1.93}}
• {{cite report|last=Gugeler|first=Russell A|year=1945|title=Army Amphibian Tractor and Tank Battalions in the Battle of Saipan|publisher=Office of the Chief of Military History|docket=8–5.3 BA|url=https://history.army.mil/documents/wwii/amsai/amsai.htm|archive-url=https://web.archive.org/web/20080103101731/https://history.army.mil/documents/wwii/amsai/amsai.htm|archive-date= 3 January 2008|type=Report}}
• {{cite journal|last=Hallion|first=Richard P.|author-link=Richard P. Hallion|year=1995|title=Prelude to Armageddon|journal=Air Power History|volume=42|issue=3

|pages=38–54|jstor=26284340}}

• {{cite thesis|last=Hemler|first=Christopher K.|year=2021|title=Learning Triphibious War: American Fire Control and Coordination in the Pacific War|degree=PhD|publisher=Texas A & M|url=https://oaktrust.library.tamu.edu/bitstream/handle/1969.1/196377/HEMLER-DISSERTATION-2021.pdf?sequence=1&isAllowed=y|archive-url=https://web.archive.org/web/20240506160316/https://oaktrust.library.tamu.edu/bitstream/handle/1969.1/196377/HEMLER-DISSERTATION-2021.pdf?sequence=1&isAllowed=y|archive-date= 6 May 2024}}
• {{cite journal|last=Hughes|first=Matthew|year=2001|title=War without mercy? American Armed Forces and the deaths of civilians during the battle for Saipan, 1944|journal=Journal of Military History|volume=75|issue=1|pages=92–123}}
• {{Cite report|last=McKinney|first=Leonard L.|year=1949|title=Portable Flame Thrower Operations in World War II|series=Chemical Corps Historical Studies|publisher=Historical Office, Office of the Chemical Corps|type=Book draft|url=https://archive.org/details/portable-flamethrower-operations}}
• {{cite conference |last=McKinnon|first=Jennifer F.|title=Inclusion and Negotiation: Interpreting Underwater Battlefield Sites for the Pacific |conference=Asia-Pacific Regional Conference on Underwater Cultural Heritage |date=8–12 November 2011 |location=Manila, Philippines |url=http://www.themua.org/collections/files/original/41493cb63c0307fe0882cb911db12c19.pdf|archive-url=https://web.archive.org/web/20150413215319/http://www.themua.org/collections/files/original/41493cb63c0307fe0882cb911db12c19.pdf|archive-date=13 April 2015}}
• {{cite conference|last=Noriaki|first=Yashiro|year=2009|title=Japanese Strategy in the Second Phase of the Pacific War |publisher=National Institute for Defense Studies, Japan|conference=International Forum on War History (Eighth Forum) – "Strategy in the Pacific War"|url=https://www.nids.mod.go.jp/english/event/forum/pdf/2009/07.pdf|archive-url=https://web.archive.org/web/20171003002552/https://www.nids.mod.go.jp/english/event/forum/pdf/2009/07.pdf|archive-date=3 October 2017|conference-url=https://www.nids.mod.go.jp/english/event/forum/forum_report.html}}
• {{cite journal|last=O'Hara|first=Vincent|author-link=Vincent O'Hara|year=2019|title=A Tale of Two Invasions|journal=Naval History Magazine|volume=33|number=3|url=https://www.usni.org/magazines/naval-history-magazine/2019/june/tale-two-invasions|archive-url=https://web.archive.org/web/20190604183926/https://www.usni.org/magazines/naval-history-magazine/2019/june/tale-two-invasions|archive-date=4 June 2019}}
• {{cite journal|last=Plung|first=Dylan J.|year=2021|title=The Impact of Urban Evacuation on Japan during World War II|journal=The Asia-Pacific Journal: Japan Focus|volume=19|issue=19 |url=https://apjjf.org/2021/19/Plung.html|archive-url=https://web.archive.org/web/20211113130437/https://apjjf.org/2021/19/Plung.html|archive-date=13 November 2021}}
• {{cite report|last=Sullivan|first=Mark P.|year=1995|chapter=Japan's Decision to Surrender|chapter-url=https://www.jstor.org/stable/resrep13891.9|title=The Mechanism for Strategic Coercion: Denial or Second Order Change?|publisher=Air University Press|pages= 31–54|jstor=resrep13891.9|type=report}}
• {{cite journal|last=Trefalt|first=Beatrice|year=2018|title=The Battle of Saipan in Japanese Civilian Memoirs: Non-combatants, Soldiers and the Complexities of Surrender|journal= Journal of Pacific History|volume=53|issue=3 |page=3|doi=10.1080/00223344.2018.1491300|url=https://www.academia.edu/97180220|url-access=registration|via=academia.edu}}

{{refend}}

{{Refbegin|30em}}

• {{cite web|title=American Memorial Park|website=National Park Foundation|url=https://www.nationalparks.org/explore/parks/american-memorial-park|archive-url=https://web.archive.org/web/20221001072833/https://www.nationalparks.org/explore/parks/american-memorial-park|archive-date=1 October 2022|ref={{SfnRef|National Park Foundation|2022}}}}
• {{Cite web |title=American Memorial Park: Battle of Saipan|url=https://www.nps.gov/amme/learn/historyculture/battle-of-saipan.htm |archive-url=https://web.archive.org/web/20220517061500/http://www.nps.gov/amme/learn/historyculture/battle-of-saipan.htm|archive-date=17 May 2022|website=National Park Service|language=en|ref={{SfnRef|American Memorial Park|2021}} }}
• {{cite web|last=Bisno|first=Adam|year=2019|title=Operation Forager: The Battle of Saipan, 15 June–9 July 1944|url=https://www.history.navy.mil/browse-by-topic/wars-conflicts-and-operations/world-war-ii/1944/saipan.html|archive-url=https://web.archive.org/web/20191206204741/https://www.history.navy.mil/browse-by-topic/wars-conflicts-and-operations/world-war-ii/1944/saipan.html|archive-date=6 Dec 2019|website=Naval History and Heritage Command}}
• {{cite news|last=Gilhooly|first=Rob|date=15 May 2011|title=Japan's Renegade Hero Gives Saipan New Hope|work=Japan Times|url=https://www.japantimes.co.jp/life/2011/05/15/general/japans-renegade-hero-gives-saipan-new-hope/|archive-url=https://web.archive.org/web/20150706001703/https://www.japantimes.co.jp/life/2011/05/15/general/japans-renegade-hero-gives-saipan-new-hope/#.VZnJBHbP32c|archive-date=6 Jul 2015}}
• {{cite web|title=International M–2–4 Rocket Truck|year=2013|website=The Marine Corps Mechanized Museum, Camp Pendleton, California|url=https://www.themech.org/vehicle/m-2-4-rocket-truck/|archive-url=https://web.archive.org/web/20200206162258/https://www.themech.org/vehicle/m-2-4-rocket-truck/|archive-date=6 Feb 2020|url-status=live|ref={{SfnRef|M–2–4 Rocket Trucks|2013}}}}
• {{cite web|url={{NHLS url|id=85001789}}|title=NHL nomination for Landing Beaches; Aslito/Isley Field; & Marpi Point, Saipan Island|publisher=National Park Service|ref={{SfnRef|National Historic Locations Application|2015}}|archive-url=https://web.archive.org/web/20191225181743/https://npgallery.nps.gov/NRHP/GetAsset/NHLS/85001789_text|archive-date=25 Dec 2019}}
• {{Cite web |url=http://pwma.o.oo7.jp/saipanirei00.html |title=サイパン慰霊祭 (Saipan Memorial Service) |website= 公益財団法人太平洋戦争戦没者慰霊協会 (Pacific War Memorial Association, inc.)|archive-url=https://web.archive.org/web/20161230085851/http://pwma.o.oo7.jp/saipanirei00.html |archive-date=30 December 2016 |url-status=dead|ref={{SfnRef|Saipan Memorial Service|2016}} }}

{{refend}}

{{Refbegin|30em}}

• {{cite book|author=Assistant Chief of Air Staff–Intelligence|year=1946|title = Mission Accomplished:Interrogations of Japanese Industrial, Military, and Civil Leaders of World War II|publisher=Headquarters, Army Air Forces|ref={{SfnRef|Mission Accomplished|1946}}|url={{Google books|id=ge5mAAAAMAAJ|pg=PA39|plainurl=yes}}}}
• {{cite report|editor-last=Crist|editor-first=David B|year=1973|orig-year=1943|title=Casablanca Conference: January, 1943|publisher=Joint Chiefs of Staff|isbn=9780160938948|url=https://www.jcs.mil/Portals/36/Documents/History/WWII/Casablanca3.pdf|archive-url=https://web.archive.org/web/20181207190900/https://www.jcs.mil/Portals/36/Documents/History/WWII/Casablanca3.pdf|archive-date=7 Dec 2018|ref={{SfnRef|Casablanca Conference|1943}}}}
• {{cite report|editor-last=Crist|editor-first=David B|year=1973|orig-year=1943|title=Quadrant Conference: August, 1943|volume=1|publisher=Joint Chiefs of Staff|isbn=9780160938832|url=https://www.jcs.mil/Portals/36/Documents/History/WWII/Quadrant3.pdf|archive-url=https://web.archive.org/web/20200613110144/https://www.jcs.mil/Portals/36/Documents/History/WWII/Quadrant3.pdf|archive-date=13 Jun 2020|ref={{SfnRef|Quebec Conference|1943}}}}
• {{cite report|author=((Joint Expeditionary Force (TF 51), Office of the Commander))|year=1944|title=Report of the Capture of the Marianas|publisher=|url=https://archive.org/details/turner-report|ref={{SfnRef|Report of Capture of Marianas|1944}}}}
• {{cite book|last=Kase|first=Toshikazu|author-link=Toshikazu Kase|year=1950|title=Journey to the Missouri: A Japanese Diplomat's Story of How His Country Made War and Peace|publisher=Yale University Press|oclc=395571}}
• {{cite report|last=Schmidt|first=Harry|author-link=Harry Schmidt (USMC)|year=1944|title=Report of Marianas Operation Phase I (Saipan)|publisher=Marine Corps Academy|url=https://www.usmcu.edu/Portals/218/Saipan-Northern%20Troops%20and%20Landing%20Force%20%20Report%2C%20August%201944.PDF|archive-url=https://web.archive.org/web/20220618162354/https://www.usmcu.edu/Portals/218/Saipan-Northern%20Troops%20and%20Landing%20Force%20%20Report%2C%20August%201944.PDF|archive-date= 18 June 2022}}
• {{cite journal|last=Sheeks|first=Robert B.|author-link=Robert B. Sheeks|year=1945|title=Civilians in Saipan|journal=Far Eastern Survey|volume=14|number=2|pages=109–113|doi=10.2307/3022063 |jstor=3022063}}
• {{Cite book|last1=Smith|first1=Holland M.|last2=Finch|first2=Percy|author1-link=Holland Smith|year=1949|title=Coral and Brass|publisher=Charles Scribner's Sons|url=https://archive.org/details/fmfrp-12-37|oclc=

367235}}

• {{cite book|last=Toyoda|first=Soemu|author-link=Soemu Toyoda|date=1946|orig-date=3 May 1944|chapter=Combined Fleet Ultrasecret Operation Order 76|editor=United States Strategic Bombing Survey, Naval analysis Division|editor-link=United States Strategic Bombing Survey|pages=226–231|title=The Campaigns of the Pacific War|publisher=Government Printing Office |url=https://archive.org/details/campaignsofpacif46unit|oclc=1041650487|ref={{SfnRef|Toyoda|1944}}}}
• {{cite book|author=United States Strategic Bombing Survey|author-link=United States Strategic Bombing Survey|year=1946|title=Interrogations of Japanese Officials|volume=2|publisher=U. S. Government Printing Office|isbn=9780598449320|oclc=3214951|url=https://www.history.navy.mil/research/library/online-reading-room/title-list-alphabetically/i/interrogations-japanese-officials-voli.html|archive-url=https://web.archive.org/web/20151117020337/https://www.history.navy.mil/research/library/online-reading-room/title-list-alphabetically/i/interrogations-japanese-officials-voli.html|archive-date=17 Nov 2015|ref={{SfnRef|Interrogations of Japanese Officials|1946}}}}

{{refend}}

{{Commons category}}

• {{cite video | year =1944 |author=United News|title =Allies Liberate Island of Elba Etc.|url =https://archive.org/details/gov.archives.arc.39017 | publisher =Universal Newsreel|time=5:55 |time-caption= Invasion of Saipan starts at| access-date =21 February 2012|ref=none}}
• {{YouTube|id=FiQUCxbHgnI|title=Battle for the Mariana Islands}}

{{Northern Mariana Islands}}

{{Authority control}}

{{Coord|15|11|N|145|45|E|region:SB_type:country_source:kolossus-cswiki|display=title}}

{{DEFAULTSORT:Saipan, Battle Of}}

Category:Mariana and Palau Islands campaign

Category:Battles and operations of World War II involving Japan

Saipan

Category:History of the Northern Mariana Islands

Category:June 1944 in Oceania

Category:July 1944 in Oceania

Category:Mass suicides

Saipan

Category:Saipan, Northern Mariana Islands

Category:United States Army in World War II

Category:United States Marine Corps in World War II

Category:World War II operations and battles of the Pacific theatre