The Military Cabinet emerged from the Prussian Army personnel department in the wake of the 1809 reform of the military, and was officially established 3 July 1814. It developed under Kaiser Wilhelm II into a personal instrument of the monarch for processing all military matters. During the First World War, the Military Cabinet lost favor to the Third Supreme Command of Hindenburg and Ludendorff. With the overthrow of the monarchy the Military Cabinet became the personnel office of the Reichswehr (army) of the Weimar Republic.