1917

January

31- Germans resume unrestricted U-boat campaign

February

23-5/5/17- Germans withdraw to the Hindenburg Line
22-25- British recapture Kut

March

1- Zimmermann telegram
11- British enter Baghdad
12- First Russian Revolution
15- Tsar Nicholas II abdicates

April

6- USA declares war on Germany; Nivelle offensive on Western Front begins
9-16- British offensive at Arras
16-20- Nivelle offensive fails
29-5/20/17- Mutinies in the French Army

May

5-15- Allied offensive on Salonika front
10- Britain introduces convoy system
12- Tenth Battle of the Isonzo begins
15- Petain becomes French commander-in-chief

June

4- Brusilov replaces Alekseev as Russian commander-in-chief
7-8- British capture Messines Ridge
12- King Constantine of Greece abdicates
25- American troops land in France

July

1- Second Brusilov offensive
20- Pact of Corfu
22- Battle of Marasti
31-11/10/17- Third Battle of Ypres (Passchedaele)

August

2- Kornilov replaces Brusilov as Russian commander-in-chief
6-20- Battle of Marasesti
19- Eleventh Battle of the Isonzo

September

1- Riga offensive
8- Kornilov coup attempt fails
27-28- Battle of Ramadi

October

24- Italians defeated at Caporetto

November

4- British forces arrive in Italy
5- Allies agree to establish a Supreme War Council at Versailles
7- Bolsheviks seize power in Russia; British seize Gaza
19- Clemenceau becomes French premier
20- British tanks gain victory at Cambrai

December

2- Fighting ends on the Eastern Front
7- USA declares war on Austria-Hungary
9- British capture Jerusalem from the Turks; Rumania signs armistice
15- Armistice signed between Germany and Russia
22- Russia and the Central Powers start peace talks at Brest-Litovsk