Major General Allen was in command of the American Forces in Germany from July 1919 until January 1923. Since May 21, 1920 he was also the American representative on the Interallied Rhineland High Commission.
For all his sympathy and compassion for France, its “military attitude” to hold Germany down for years greatly worried him as it would rather bring about new conflicts and suffering than peace and restoring in Europe.
The AFG was playing a crucial stabilizing role. Firmly believing in the AFG’s mission, the General stood for continuing the U.S. deployment on the Rhine even when most Americans, including President Harding, wanted to recall all American troops from the Rhine.
Eventually, in January 1923, Congress decided to reduce all American troops. A couple of days later, French and Belgian troops occupied the Ruhr area. On January 24, 1923, the American flag was lowered from the historic Fortress Ehrenbreitstein and the last American forces departed from Germany. General Allen gave his final speech, probably with worries: “With deep affection in our hearts for our Allies and sympathy for our former foes, our highest ambition has been to act with such justice towards all as would insure a lasting peace in Europe.”
In 1922, General Allen saved Ehrenbreitstein fortress from being destructed.