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• April 21 – Bardas, the regent of the Byzantine Empire, is murdered by Basil the Macedonian at Miletus, while conducting a large-scale expedition against the Saracen stronghold of Crete.

• May 26 – Basil the Macedonian is crowned co-emperor of the Byzantine Empire, and is adopted by the much younger Michael III.

• May 27 – King Ordoño I, ruler of the Kingdom of Asturias, dies after a 16-year reign. He is succeeded by his son, Alfonso III, who later is referred to as "Alfonso the Great".
• July 2 – Battle of Brissarthe: Frankish forces, led by Robert the Strong, are defeated by a joint Breton-Viking army.
• Louis II, Holy Roman Emperor, defeats the Saracen invaders who are ravaging southern Italy.

• The Great Heathen Army of the Vikings rides north to Northumbria. The Northumbrians are preoccupied with a civil war, and the Danes enter York unopposed.John Haywood (1995). Historical Atlas of the Vikings, p. 62. Penguin Books: {{ISBN|978-0-140-51328-8}}

• An army in Lucera is assembled by orders of Louis II in preparation for an attack on the Emirate of Bari.{{Cite book |last=Purton |first=Peter |url=https://doi.org/10.1017/9781846158032 |title=A History of the Early Medieval Siege, c.450–1220 |date=2010-03-18 |publisher=Boydell and Brewer Limited |isbn=978-1-84615-803-2}}

• October 17 – Caliph al-Musta'in is put to death, after a 4-year reign. He is succeeded by al-Mu'tazz, who becomes the youngest Abbasid caliph to assume power.History of the Arabs by Philip K. Hitti.
• The Kharijite revolt against the Abbasid Caliphate begins in Al-Jazira (Upper Mesopotamia), which will last for 30 years.

• Fujiwara no Yoshifusa becomes regent (sesshō) to assist the child emperor Seiwa, starting the Fujiwara regency.

• Boris I, ruler (knyaz) of the Bulgarian Empire, sends a diplomatic mission, led by the Bulgarian nobleman Peter, to Rome, in an effort to renew ties with the West.
• Pope Nicholas I orders that all Catholics should abstain from eating the "flesh, blood, or marrow"{{cite news|title=Beyond the Trivia - Fish Fridays|url=https://krcgtv.com/features/beyond-the-trivia/beyond-the-trivia-fish-fridays#:~:text=It%20was%20Pope%20Nicolas%20I,in%20memory%20of%20Christ's%20death.|first=Preston|last=Dick|publisher=KRCG|date=2023-02-24|access-date=2023-03-01}} of warm-blooded animals on Wednesdays and Fridays.{{cite web|title=How Did the Roman Catholic Tradition of Eating Fish on Fridays Begin?|date=March 15, 2019 |url=https://kofc5357.org/2019/03/15/how-did-the-roman-catholic-tradition-of-eating-fish-on-fridays-begin/|access-date=2023-03-01}}
• Pope Nicholas I forbids the use of torture in prosecutions for witchcraft (approximate date).

• June 10 – Uda, emperor of Japan (d. 931)
• September 19 – Leo VI, Byzantine emperor (d. 912)
• Carloman II, king of the West Frankish Kingdom (approximate date)
• Robert I, king of the West Frankish Kingdom (d. 923)
• Yao Yi, chancellor of Later Tang (d. 940)

• April 21 – Bardas, Byzantine chief minister and regent
• May 27 – Ordoño I, king of Asturias
• June 21 – Rodulf, Frankish archbishop
• July 2 – Robert the Strong, Frankish nobleman
• July 16 – Irmgard, Frankish abbess
• October 17 – Al-Musta'in, Abbasid caliph
• Adelaide of Tours, Frankish noblewoman
• Al-Mu'ayyad, Abbasid prince
• Charles the Child, king of Aquitaine
• Eberhard, duke of Friuli
• Emenon, Frankish nobleman
• Hungerus Frisus, bishop of Utrecht
• Linji Yixuan, Chinese monk and founder of the Linji school
• Liudolf, duke of Saxony
• Ranulf I, Frankish nobleman (b. 820)
• Robert, Frankish nobleman (b. 834)
• Rudolph, Frankish nobleman
• Wang Shaoyi, general of the Tang Dynasty
• Yahya ibn Yahya, Idrisid emir of Morocco{{EI2 | last = Eustache | first = D. | title = Idrīsids | volume = 3 | pages = 1035–1037 | doi =10.1163/1573-3912_islam_SIM_3495}}

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