The Operation Faustschlag, also known as the Eleven Days' War, was a Central Powers offensive in World War I. It was the last major action on the Eastern Front. Russian forces were unable to put up any serious resistance due to the turmoil of the Russian Revolution and subsequent Russian Civil War. The armies of the Central Powers therefore captured huge territories in Estonia, Latvia, Belarus, and Ukraine, forcing the Bolshevik government of Russia to sign the Treaty of Brest-Litovsk.