Ypres east of the town. The first gas attack occurred against Canadian, British, and French soldiers, including both metropolitan French soldiers as well as Senegalese and Algerian tirailleurs (light infantry) from French Africa. The gas used was chlorine. Mustard gas, also called Yperite from the name of this town, was also used for the first time near Ypres, in the autumn of 1917. Of the battles, the largest, best-known, and most costly in human suffering was the Third Battle of Ypres (31 July to 6 November 1917, also known as the Battle of Passchendaele), in which the British, Canadian, ANZAC, and
3rd Army (German Empire) May 1917. Einem's right wing units would also participate in Erich Ludendorff's Champagne-Marne offensive on 15–17 July 1918 supporting the east flank of the German 1st Army. After suffering severe casualties in battle with John J. Pershing's Allied Expeditionary Force from 26 September – 11 November in the Meuse-Argonne offensive, the army was forced to retreat northward shortly before the war's end. At the end of the war it was serving as part of "Heeresgruppe Deutscher Kronprinz". By the end of the war, the 3rd Army was organised as: The 3rd Army had the following commanders during its existence: 3rd