Submarines

Submarines played a major role in World War II. The invention of electric motors in the 1880s and of internal combustion engines in the early 1900s made the submarine a practical vessel, and by the time of World War I, submarines had made major advances, able to reach surface speeds of 16 knots and 10 knots submerged, and carrying crews of 35 or more. Armed with torpedoes and deck guns, submarines revolutionized sea warfare and posed new dangers to merchant shipping. The Germans, in particular, excelled at such warfare and in World War I their U-boats threatened Allied commerce and the viability of the British blockade.

During World War II, the Germans, Americans, British, Japanese, and Italians launched several thousand larger and more powerful “blue water” boats capable of high seas operation and difficult to detect. Crew sizes, tonnage, and lethality doubled. Germany built more than 1,160 U-boats and seriously contested Allied control of the Atlantic between 1939 and 1943. During the Battle of the Atlantic, Germany lost some 785 submarines, more than any other belligerent—but the U-boats also sank nearly 2,600 Allied merchantmen totaling some 14.5 million tons gross weight.

British submarines sank 169 warships and 493 merchant vessels, while suffering 74 losses, about 33 percent of the total British submarine force during the war. In the Mediterranean, British submarines impeded the supply of Axis forces in the North African campaign, contributing significantly to their May 1943 defeat. Although Italy possessed some 150 submarines, vastly superior British antisubmarine tactics restricted their use, and 86 Italian submarines were lost with only six enemy warships and 500,000 tons of destroyed merchant shipping claimed in return.

U. S. Navy submarines in the Pacific destroyed Japanese merchant shipping between 1943 and 1945 to the point that enemy offensive operations were made impossible. Although having to overcome early defects in torpedo design, the 288 U. S. submarines sank nearly 1,300 Japanese merchantmen as well as one battleship, eight aircraft carriers, and 11 cruisers. Fifty-two American submarines were sunk. The 200 submarines ultimately comprising Japan’s submarine force did not register significant successes, although they sank a score of American warships and about 170 merchant and transport vessels while losing 128 of their own.

Little is known of Soviet submarines during the war, although they were active in the Baltic and Black Sea areas. With Soviet submarines technologically inferior to the boats of other powers, it has been speculated that the Soviets lost one submarine for each enemy ship sunk.

Further reading: Erminio Bagnasco, Suh-marines of World War II (Annapolis, Md.: Naval Institute Press, 1977); Norman Friedman, U. S. Suhmarines through 1945: An Illustrated Design History (Annapolis, Md.: Naval Institute Press, 1995); Brayton Harris and Walter J. Boyne, The Navy Times Book of Suhmarines: A Political, Social, and Military History (New York: Berkeley, 1997).

—Clayton D. Laurie