Hans-Diedrich Freiherr von Tiesenhausen was a German Kapitänleutnant with the Kriegsmarine during World War II. He was also a recipient of the Knight's Cross of the Iron Cross (German: Ritterkreuz des Eisernen Kreuzes). The Knight's Cross of the Iron Cross was awarded to recognise extreme battlefield bravery or successful military leadership.

Tiesenhausen sailed with the U-23 and U-331. He achieved his greatest success as a U-boat commander by sinking the British battleship HMS Barham on 25 November 1941. On his 3rd patrol U-331 returned to the Egyptian coast.

On 17 November she landed seven men of the Lehrregiment Brandenburg east of Ras Gibeisa, on a mission to blow up a railway line near the coast, which failed.

U-331 was sunk on 17 November 1942, north of Algiers, during "Operation Torch". She had been badly damaged after being attacked by a Lockheed Hudson bomber and signalled surrender, but was attacked and sunk by a Fairey Albacore torpedo-bomber from the British aircraft carrier HMS Formidable. Of her crew 32 were killed and 17 survived including Tiesenhausen. He was a prisoner of war in England and Canada until 1947 when he returned to Germany. He worked as a joiner, but in late 1951 he returned to Canada.[3]

Awards

• Dienstauszeichnung 4th Class (8 April 1938)[4]
• The Return of Memel Commemorative Medal (25 June 1940)[5]
• The Return of Sudetenland Commemorative Medal of 1 October 1938 (6 September 1940)[5]
• Iron Cross (1939)
  • 2nd Class (30 January 1940)[5]
  • 1st Class (7 December 1941)[5]
• Medaglia di bronzo al Valore Militare (November 1941)[5]
• Medaglia d'Argento al Valor Militare (25 March 1942)[5]
• U-boat War Badge (1939) (26 February 1942)[5]
• Knight's Cross of the Iron Cross on 27 January 1942 as Kapitänleutnant and commander of U-331[6]
• Mentioned twice in the Wehrmachtbericht on 26 November 1941 and 27 January 1942