Oberste Heeresleitung

After discovering that the armies were separated from each other by a gap of 25 mi (40 km) and in danger of being encircled, Hentsch ordered a retreat to the Aisne.

Moltke was replaced by the Prussian Minister of War, Lieutenant General Erich von Falkenhayn, first informally in September and then officially on 25 October 1914.

Falkenhayn centralised decision making and emphasised secrecy, rarely explaining himself to his subordinates, which has caused historians difficulty in assessing his intentions.

As the French position became desperate, Falkenhayn expected a British relief effort near Arras which would be destroyed, leaving the remnants of both armies to be mopped up.

[11][a] The duumvirate increasingly dominated decision making on the German war effort, to an extent that they are sometimes described as de facto military dictators, supplanting the Emperor and Chancellor Theobald von Bethmann Hollweg, whom they managed to have replaced with Georg Michaelis in the summer of 1917.

Ludendorff ordered the resumption of the unrestricted U-boat Campaign, which, along with the Zimmermann Telegram, provoked the United States to enter the war.

After the October coup, the OHL negotiated the Treaty of Brest-Litovsk to free troops for the 1918 German spring offensive on the Western Front.

As the tide of the war turned against Germany with the Allied Hundred Days Offensive, in late September 1918, Ludendorff called for the "parliamentarisation" of the German government and immediate armistice negotiations.

Groener subsequently came to an agreement with the Social Democrat leader Friedrich Ebert known as the Ebert–Groener pact under which the Army leadership agreed to back the new republican government.

With the war over in November 1918, the OHL was moved from Spa to Schloss Wilhelmshöhe in Kassel, to supervise the withdrawal of the German armies from the occupied territories.

[13] The final location of the OHL was at Kolberg after February 1919 as the military focus had shifted to preventing territorial encroachment by the Second Polish Republic.