Amasis was built as a combined passenger and cargo ship and operated for the Hamburg-America Line, HAPAG. However, when the war began, the ship was re-commissioned by the Kriegsmarine.

On April 7, 1940, Amasis left Stettin at 2 in the morning together with the convoy Seetransportstaffel 1, which was headed for Oslo in Norway with various military supplies. The transport ship Antares was in the same convoy along with three additional transport ships.

On April 9, the British, through their aerial reconnaissance, had learned that German ships were heading north through the Kattegat, and the British submarine HMS Sunfish, which had left England a few days earlier to patrol in the Kattegat, had been informed about the ships and was waiting at Måseskär. From the submarine, Amasis was observed on April 10 at 16:30. At 17:19, the submarine fired two torpedoes. From Amasis, a periscope and a torpedo were observed in the water heading towards the ship. One of the torpedoes hit Amasis midship on the starboard side, and the ship began to sink. After Sunfish fired the torpedoes, it was quickly forced to dive due to the German aircraft in the air. All 51 people who were on board Amasis at the time were rescued. The last left the ship around 21:00 in the evening. Amasis stayed afloat until 03:00 on the morning of April 11 when it sank bow-first.

At the time, Amasis was loaded with coal and was in Swedish and thus neutral waters to avoid hostile ships. On board, there was a Swedish pilot to navigate the ship through neutral waters. The crew on board Amasis was brought ashore and shortly after, they were sent back to Germany.

On the starboard side behind the superstructure, the ship is devastated by the torpedo explosion. At the stern, there is a large double wheel. Many fine valves, large square ones.