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
French Army in World War I German army in August 1914; however, the Germans were the first to seriously research chemical warfare. Poison gas (chlorine) was first used on April 22, 1915, at the Second Battle of Ypres, by the German army. April 1915 saw the first innovation in protection against chemical warfare: a cotton pad dipped in bicarbonate of soda, but by 1918, troops on both sides had charcoal respirators. By November 11, 1918, France had suffered 190,000 chemical warfare casualties, including 8,000 dead. At the outbreak of war the French Army retained the colourful traditional uniforms of the nineteenth century for active service wear.