After the war, "Marlborough" was assigned to the Mediterranean Fleet, where she took part in the Allied intervention in the Russian Civil War in the Black Sea in 1919–20, and she rescued members of the Imperial Family from Yalta in 1919. She was also involved in the Greco-Turkish War. In 1930, the London Naval Treaty mandated that the four "Iron Duke"-class battleships be discarded; "Marlborough" was used for a variety of weapons tests in 1931–32, the results of which were incorporated into the reconstruction programme for the s.