During the German assault on the Soviet Union, the Soviet battleships served as convoy escorts during the evacuation of Tallinn, and as floating batteries during the siege of Leningrad.[18] The dense German and Finnish minefields and the submarine nets effectively restricted Soviet traffic in the Gulf of Finland, forcing the larger vessels to remain at port.[18][19] The German Stuka pilot Hans-Ulrich Rudel eventually sank Marat at her moorings on 23 September 1941.