The 1918 Spring Offensive or Kaiserschlacht (Kaiser's Battle), also known as the Ludendorff Offensive, was a series of German attacks along the Western Front during World War I, beginning on March 21, 1918 which marked the deepest advances by either side since 1914. The Germans had realised that their chance of victory was at hand. They also had the advantage in numbers afforded by the nearly 50 divisions freed by the Russian surrender (the Treaty of Brest-Litovsk).