Oberste Heeresleitung
The Oberste Heeresleitung (German pronunciation: [ˈoːbɐstə ˈheːʁəsˌlaɪtʊŋ], Supreme Army Command or OHL) was the highest echelon of command of the army (Heer) of the German Empire. In the latter part of World War I, the Third OHL assumed dictatorial powers and became the de facto political authority in the empire.
After the formation of the German Empire in 1871, the Prussian Army, Royal Saxon Army, Army of Württemberg and the Bavarian Army were autonomous in peacetime, each kingdom maintaining a separate war ministry and general staff to administer their forces. On the outbreak of war, the Constitution of the German Empire made the Emperor Commander-in-Chief of the combined armies (Oberster Kriegsherr, Supreme Warlord).
Upon mobilizing in 1914 at the outbreak of World War I, the Großer Generalstab (Great General Staff) formed the core of the Supreme Army Command, becoming the General Staff of the Field Army. The Emperor's role as Commander-in-Chief was largely ceremonial and authority lay with the Chief of the General Staff, who issued orders in the Emperor's name. The pre-war Chief of the General Staff was Colonel General Helmuth von Moltke (The Younger) and the Oberste Heeresleitung was the command staff led by Moltke as Chief of the General Staff of the Army.
For most of the war, OHL was located at Spa in Belgium. In addition to the General Staff of the Field Army, the Supreme Army Command consisted of the Emperor's Military Cabinet, the Intendant General (responsible for supply), senior advisers in various specialist fields (Artillery, Engineers, Medicine, Telegraphy, Munitions and Railways) and representatives from the four German War Ministries and representatives of the other Central Powers. The Emperor was also Commander-in-Chief of the Imperial German Navy, which was led by the German Imperial Admiralty Staff and from August 1918 by the Seekriegsleitung (SKL, Naval Warfare Command). Co-ordination was poor at the beginning of the war between OHL and SKL, the navy did not even know about the Schlieffen Plan, an initial attack on France through Belgium.
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