world war 1 in 1915

  • January 1 - March 30

    Allied offensive in Artois and Champagne
  • January 15

    Japan's 21 demands on China
  • January 19-20

    First German zeppelin attack on England
  • February 4

    German U-boat attacks on Allied and neutral shipping; declares blockade of Britain
  • February 7-21

    Russians suffer heavy losses at Second Battle of Masurian Lakes (also known as the Winter Battle)
  • February 19-August

    Allied amphibious attack on the Dardanelles and Gallipoli (initiated by Winston Churchill, who resigns as a consequence) ends with the Turkish siege of the Allied forces
  • March 1

    First passenger ship sinks, the British liner Falaba
  • March 11

    Britain announces blockade of German ports
  • February - April

    Austro-Hungarian attack on Russian Poland (Galicia) collapses, with the Russians counterattacking
  • April-June

    Germans focus on Eastern Front, breaking through Gorlice-Tarnow and forcing Russia out of much of Poland
  • April 22 - May 25

    First use of poison gas by Germany starts Second Battle of Ypres
  • April 25

    Allied landing at Gallipoli
  • April 26

    France, Russia, Italy and Britain conclude secret Treaty of London
  • May 2

    Austro-German offensive on Galicia begins
  • May 7

    U-boat sinks British liner Lusitania with the loss of American lives, creating a US-German diplomatic crisis
  • May 9

    Second Battle of Artois begins
  • May 23

    Ignoring treaty agreements with the Central Powers, Italy declares war on Austria-Hungary
  • May 25

    British Prime Minister Asquith reorganises his Liberal government as a coalition of the parties
  • June 29 - December 2

    Italians launch unsuccessful attack on Hungarians at 1st, 2nd, 3rd & 4th Battles of Isonzo; there are to be 12 in total
  • August 4

    Germans capture Warsaw
  • September 5

    Tsar Nicholas takes command of Russian armies
  • September 22

    Second Battle of Champagne begins
  • October 3

    Anglo-French force lands at Salonika in Greece
  • October - November

    austro-German-Bulgarian forces invade Serbia, expelling Serbian army from the country
  • December 19

    Sir Douglas Haig replaces Sir John French as commander of British Expeditionary Force
  • December 28

    Allies begin withdrawal of troops from Gallipoli