February 4 - In early November 1914 the British had established a naval blockade of Germany to starve it of vital resources and food. In response, on February 4, 1915 Germany declared that all waters around Great Britain and Ireland, including the whole of the English Channel, are a War Zone. Every Allied ship - merchant or warship - in this zone may be attacked without warning. The Germans send out 20 U-boats to enforce the naval blockade. German U-Boats sank 756 ships in 1915, almost two a day

February 7 -22 On the Eastern Front, a combined German-Austrian force decisively defeats the Russian First Army at the Second Battle of the Masurian Lakes. German and Austrians forces make a wide advance and penetrate 200 km into Russian territory. Russian forces endure severe losses.

February 19 - The French and British navies attempt to put the Ottoman Empire out of the war, by forcing open the Dardanelles Straits. The campaign is a costly failure. Seven Allied battleships are severely damaged or sunk.

March 10-13 - The Battle of Neuve Chapelle. This was the first planned British offensive in the war. The attack achieved little success but it taught the British a great deal about what was required to fight a major battle. The Canadians played minor role as a diversionary force

April - The First Canadian Division moves to the Ypres Salient.