The steamer Cardiff was en route from Cardiff, Wales to St. Nazaire on January 10, 1918 with a load of good Welsh coal when she was torpedoed by SMS U-84 northwest of Belle Île, France. The twenty year old ship probably should have sunk, but her master managed to put her aground and save the ship. Even though the ship did not sink, the powerful explosion killed eight of the crew.

She was refloated and repaired and served another twenty-four years. In the next war Cardiff was sailing under a new name, Konsul Schulte, she was now owned by a company in Germany. While the Germans could not sink her in the Great War, she did not survive the Second World War. On Feb. 5, 1942 she was again torpedoed, this time by a Soviet submarine. Shch-421 and Lt. Cdr. Lunin sent her to the bottom in Porsanger Fjord, Norway.

The original attack was made by Kapitänleutnant Walter Roehr, who attacked only two further ships, sinking only one. Roehr, his crew and U-84 never returned from the patrol. During his career Roehr and U-84 (his only command) had destroyed over 83,000 tons of shipping.