Wikipedia:WikiProject Military history/News/September 2015/World War I timeline

| style="background:darksalmon; width:100px;" | Eastern

| style="background:yellowgreen; width:100px;" | Italian

| style="background:khaki;" | Middle Eastern

| style="background:lightgreen;" | Balkan

| style="background:cornflowerblue;" | Naval

| style="background:lightskyblue;" | Air

| style="background:yellow;" | Asian and Pacific

| style="background:red;" | Gallipoli

| January 19 – December 22

|Battle of Hartmannswillerkopf, series of battles fought to control the peak.

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| June–September

| The Russian Great Retreat from Poland and Galicia.

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| August 26 – September 19

| Sventiany Offensive, a phase of the Gorlice-Tarnow Offensive.

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| September 1

| Germany suspends unrestricted submarine warfare.

| Details

| September 8

| Nicholas II removes Grand Duke Nicholas Nikolayevich as Commander-in-Chief of the Russian Army, personally taking that position.

| Details

| September 15 – November 4

| Third Battle of Artois.

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| September 19

| The Germans occupy Vilnius. The Gorlice-Tarnów Offensive ends.

| Details

| September 25–28

| Battle of Loos, a major British offensive, fails.

| Details

| September 25 – October 15

| Battle of the Hohenzollern Redoubt, a phase of the Battle of Loos.

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| September 25 – November 6

| Second Battle of Champagne.

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| September 28

| Battle of Es Sinn.

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