Ralf-Reimar Wolfram was a German

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 Korvettenkapitän during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

. During his career he commanded two U-boats for a total of 118 days at sea spanning four patrols. During his third patrol he successfully sunk the , an American liberty ship

Liberty ship

Liberty ships were cargo ships built in the United States during World War II. Though British in conception, they were adapted by the U.S. as they were cheap and quick to build, and came to symbolize U.S. wartime industrial output. Based on vessels ordered by Britain to replace ships torpedoed by...

. Robert Gray was a part of American convoy HX 234 en route to London.

For Wolfram's fourth patrol, he commanded U-864 during Operation Caesar

Operation Caesar

Operation Caesar was a secret mission carried out by Germany in World War II to supply Germany's faltering ally, Japan, with advanced technology to fuel their war machine...

. He was killed when his submarine was sunk by the British submarine, HMS Venturer

HMS Venturer (P68)

HMS Venturer was a Second World War British submarine.-Construction:Venturer was the lead boat of the British V class submarine, a development of the successful U-class...

. This was the only known instance of one submerged submarine sinking another submerged submarine. U-864 remains Wolfram's grave to this day.