British war crimes September 1915 and continued their usage for the remainder of the war. This was done in retaliation for the use of chlorine by Imperial German Army the preceding April. Following the Imperial German Army's use of poison gas at Ypres, the commander of II Corps, Lieutenant General Sir Charles Ferguson, had said of poison gas: Mustard gas was first used effectively in World War I by the German army against British and Canadian soldiers near Ypres, Belgium, in 1917 and later also against the French Second Army. The name "Yperite" comes from its usage by the German army near the
18th Army (German Empire) 18th Army (German Empire) <nowiki></nowiki> The 18th Army () was an army level command of the German Army in World War I. It was formed against France on 27 December 1917 from the former Heeresgruppe Woyrsch command. It served exclusively on the Western Front and was dissolved on 2 January 1919. 18th Army was one of three armies (along with 17th Army and 19th Army) formed in late 1917 / early 1918 with forces withdrawn from the Eastern Front. They were in place to take part in Ludendorff's Spring Offensive. The Germans had realised that their only remaining chance of