Portsmouth Naval Prison - Office of Naval Intelligence

Office of Naval Intelligence

After German surrender ended World War II fighting in Europe on May 5, 1945, U-boats surrendering to United States naval forces were escorted to Portsmouth so engineers at the Portsmouth Naval Shipyard might study their design features. U-805, U-873, U-1228 and U-234 were towed to the Portsmouth Naval Shipyard between 15 and 19 May. The Office of Naval Intelligence (ONI) had interrogators available to question the submarine crewmen at the prison. The interrogations were classified at the time because of potential military value of information collected about German submarine, jet aircraft, ballistic missile, guided bomb, and nuclear weapons technology. U-234 had been bound for Japan carrying 1,232 lb (559 kg) of uranium oxide, a disassembled Messerschmitt Me 262 jet fighter, tons of prototypes and technical documents relating to new weapons, and several senior weapons technicians. The commanding officer of U-873 had conducted submarine-launched ballistic missile experiments with his brother Ernst Steinhoff, who was Director for Flight Mechanics, Ballistics, Guidance Control, and Instrumentation at the Peenemünde Army Research Center. Kapitänleutnant Friedrich Steinhoff was slapped by a large, husky Marine guard until his face was swollen and bleeding, and died in a Charles Street Jail cell after two days of interrogation. Despite subsequent declassification of documents, it is unclear if ONI realized Steinhoff's ballistic missile connections. Similar uncertainty remains about disposal of the uranium oxide aboard U-234.

There was inadequate preparation to deal with the arriving U-boats. United States Navy prize crews scattered possessions of the U-boat crewmen as they searched for potential sabotage and intelligence information while the U-boats were enroute to Portsmouth. Scattered documents and clothing were perceived as fire and access hazards while the U-boats awaited inspection by shipyard engineers. Material scattered aboard the U-boats was stockpiled in the prison entrance lobby where it was looted by prison guards. Decorations and personal possessions taken from U-boat crewmen were retained as souvenirs rather than returned to prisoners of war as required by the Geneva Convention.