Ober Ost is short for Oberbefehlshaber der gesamten Deutschen Streitkräfte im Osten, which is a German term meaning "Supreme Commander of All German Forces in the East" during World War I. In practice it refers not only to said commander, but also to his governing military staff and the district they controlled: Ober Ost was in command of the Eastern front. After the Treaty of Brest-Litovsk the German Empire effectively controlled  Lithuania, Latvia, Belarus, parts of Poland, and Courland: former territories of the Russian Empire. Ober Ost itself was assigned present-day Lithuania, Latvia, Belarus, Poland, and Courland. The land it controlled was around 108,808 km². The Ober Ost was created in 1914, and its first leader was Paul von Hindenburg, a Prussian military hero. When the Chief of the General Staff Erich von Falkenhayn was dismissed from office in 1916, von Hindenburg replaced him, and Prince Leopold of Bavaria was given control of the Ober Ost.