During WW1 (the Great War, 1914-1918), Spa operated as an important German convalescent hospital town between 1914 and 1917. The general headquarters of Kaiser Wilhelm II was, in 1918, the last place where he resided before his abdication due to the German surrender. In July 1920 the town hosted the Spa Conference, a meeting of the Supreme Council. German delegates were invited to this to discuss war reparations.