
On this day in 1941, German U-boat (submarine) U-47 disappeared off the west coast of Ireland. Captained by “U-Ace” Günther Prien, the submarine was one of the most infamous of its kind. During his short career, Prien and the 44 crewmembers of U-47 sank 30 Allied merchant vessels, destroying over 200,000 gross register tons (GRT) of supplies and killing huge numbers of Allied seamen. In February of 1941 – soon after the fall of France and a period of high German morale – U-47 set off on its tenth combat patrol. Accompanied by other U-boats in a Wolfpack formation, U-47 became separated from the group on March 7th and began engaging Allied convoy OB 293 with torpedos. After 5 hours of pursuit, U-47 was hit by depth charges from the HMS Wolverine and exploded beneath the surface, killing all on board.

Just like accomplished Luftwaffe pilots, successful U-boat captains of the Kriegsmarine (navy) were granted hero status in Nazi Germany. Before the Allied landings on Normandy in 1944, much of the worst combat in Europe took place on the high seas. German command understood that the Allies possessed the greater navy, and far superior logistical capabilities; so, Hitler’s primary means for disrupting the Allied war effort was attacking merchant shipping lines. In July of 1941, German codes were cracked, enabling the Allies to predict U-boat manoeuvres (something the Kriegsmarine never figured out). Until that point, however, U-boats remained one of the most dangerous tools in Hitler’s arsenal. After the war, British PM Winston Churchill recalled that “...the only thing that ever really frightened me during the war was the U-boat peril.”