Germany began extensive submarine warfare as a strategy to cut off supplies to England before the United States or other neutral powers could enter World War I.

At the beginning of World War I, the first sea lord of the British Admiralty, Vice Admiral Prince Louis of Battenberg, established patrols in the southern North Sea to protect the eastern entrance of the English Channel against raids by German destroyers and minelayers. The force assigned to this task included two flotillas of destroyers and a squadron of five old armored cruisers, but the risk of attack by German submarines was not actually taken very seriously. On September 5, 1914, however, the British light cruiser HMS Pathfinder was sunk by the German submarine U-21 off the Firth of Forth, and on September 13, the British submarine E-9 destroyed the German light cruiser Hela off Heligoland. It should have been apparent that submarines were making a significant appearance in the war and would have to be regarded as a serious danger to surface ships, but the Admiralty did nothing to alter the dispositions of the southern patrol. U-boats[U boats]
Submarines;World War I[World War 01]
Ships;submarines
World War I (1914-1918)[World War 01];submarine warfare
[kw]Germany Begins Extensive Submarine Warfare (Sept. 22, 1914)
[kw]Submarine Warfare, Germany Begins Extensive (Sept. 22, 1914)
[kw]Warfare, Germany Begins Extensive Submarine (Sept. 22, 1914)
U-boats[U boats]
Submarines;World War I[World War 01]
Ships;submarines
World War I (1914-1918)[World War 01];submarine warfare
[g]Germany;Sept. 22, 1914: Germany Begins Extensive Submarine Warfare[03600]
[c]Science and technology;Sept. 22, 1914: Germany Begins Extensive Submarine Warfare[03600]
[c]Wars, uprisings, and civil unrest;Sept. 22, 1914: Germany Begins Extensive Submarine Warfare[03600]
[c]World War I;Sept. 22, 1914: Germany Begins Extensive Submarine Warfare[03600]
[c]Military history;Sept. 22, 1914: Germany Begins Extensive Submarine Warfare[03600]
Mountbatten, Louis
Campbell, Henry H.
Weddigen, Otto

The crew of a German submarine posing on their vessel in 1916.

(Library of Congress)

On September 22, three ships of the British Seventh Cruiser Squadron, HMS Aboukir, Cressy, and Hogue, were patrolling west of the Dutch coast. The squadron commander, Admiral Henry H. Campbell, was on his flagship, which was refueling in port. When bad weather drove the escorting destroyers into port, the three cruisers were left without escort. In accordance with the admiral’s orders, they were steaming on a straight course at less than ten knots. Shortly after sunrise, they were sighted by Otto Weddigen, captain of the German submarine U-9. At 6:30 a.m., the submarine hit the Aboukir with a single skillfully directed torpedo. The cruiser quickly took on a dangerous list.

The captain of the Aboukir, Captain John E. Drummond, believed that he had hit a mine, and, being the senior officer present, he ordered the other two ships to close in on him. The Hogue neared the sinking ship, came to a stop, and launched boats to rescue the crew of the Aboukir. U-9 then took aim at the stationary Hogue and fired again at close range. Two torpedoes hit and mortally wounded the Hogue. Meanwhile, the Aboukir capsized and sank. Ten minutes later, the Hogue also foundered, and the survivors joined those from the Aboukir in the sea. Unwilling to abandon the struggling men, R. W. Johnson, captain of the remaining ship Cressy, brought his vessel to a dead stop, thereby providing Weddigen with a helpless target. Weddigen did not miss the opportunity; he reloaded his torpedo tubes and fired three times at the Cressy. Two torpedoes exploded against the ship, ripping out its side. The cruiser sank in fifteen minutes. In little more than an hour, Weddigen had accounted for three 12,000-ton armored cruisers with his small 493-ton ship manned by twenty-nine men. British loss of life was extremely heavy; fourteen hundred men out of the twenty-two hundred in the crews of the three ships were either killed or drowned.

Shortly afterward, German submarines began to attack merchant vessels and proved themselves highly effective, and inhumane, destroyers of commerce. On October 20, 1914, U-17 sank the British Glitra; it was the first of more than 13,000 merchant ships, 36 million tons in all, to be sunk by submarines of all navies in both world wars. In 1917, the Germans inaugurated a campaign of unrestricted submarine warfare. “Unrestricted” meant that the U-boats did not observe the rules of international law, which prescribed that warships must search merchantmen suspected of carrying contraband before sinking them and that merchant ships must not be sunk at all if the crew could not first be put in a safe place. It was this offensive against civilian shipping, deemed brutish and cowardly by the standards of those days, that brought the United States into the war against Germany. Meanwhile, through unrestricted torpedo attacks and by laying mines, in the first four months of 1917 German submarines sank no fewer than 1,147 ships totaling more than 2.2 million tons, forcing Great Britain to face the possibility of starvation and defeat. The British responded by collecting their merchant ships into convoys that could be protected directly by escorting warships.

Germany’s risky strategy—attempting to use U-boats to isolate and blockade Britain into submission before accidental sinkings of noncombatants could bring neutrals such as the United States into the war—failed. The sinking of the passenger liner Lusitania
Lusitania (ship)
Ships;Lusitania on May 7, 1915, with more than one hundred Americans aboard, was met with sharp rebukes and general threats from Washington, D.C. Other sinkings, including those of the Arabic in August, 1915, and the Sussex six months later, were followed by outrage in the United States and promises by Germany to end “unrestricted submarine warfare.” When it became clear that Germany actually had no intention of ordering a change in tactics for the U-boats, the United States entered the war in April, 1917.

At first, a certain amount of disdain existed for submarine warfare, as many believed that it was not an “honorable” way to fight. The nations of the world soon decided, however, that the areas beneath the ocean surfaces were as much a part of the military map as those above, and they devised strategies accordingly. Admiralty staffs started to procure submarines and plan for their use. Likewise, those charged with defending against submarine attacks developed new strategies.

In World War II, World War II (1939-1945)[World War 02];submarine warfare the British and their allies used the convoy system from the beginning of hostilities. The Germans retaliated by grouping their U-boats into packs, and great actions were fought between five or ten submarines and the convoy escorts in the grim Battle of the Atlantic. In 1942 alone, German submarines sank 1,054 ships totaling more than 5.7 million tons, seriously impeding the offensive capacity of the Allies. In the Mediterranean, British submarines dispatched a quarter of the entire Italian merchant marine, thus helping to cut off the Italo-German armies in Libya from their sources of food, fuel, and ammunition.

During World War II, antisubmarine warfare efforts featured new “combined arms” approaches utilizing aircraft and surface ships; by the 1950’s, other submarines were used to track and sink submarines. By the 1960’s and 1970’s, attack submarines became a focal point of the antisubmarine warfare battle, especially against ballistic missile submarines. U-boats[U boats]
Submarines;World War I[World War 01]
Ships;submarines
World War I (1914-1918)[World War 01];submarine warfare

• Gibson, R. H., and Maurice Prendergast. The German Submarine War, 1914-1918. 1931. Reprint. Annapolis, Md.: Naval Institute Press, 2003. Objective account of the U-boats in World War I includes an estimate of their effectiveness in the conflict. Discusses the development and evolution of the U-boat before World War I and speculates about the effectiveness of submarines in future conflicts.
• Gray, Colin S. The Leverage of Sea Power: The Strategic Advantage of Navies in War. New York: Free Press, 1992. Classic analysis of the effect of sea power on land conflicts provides an excellent overview of the topic. Includes discussion of submarine warfare.
• Macintyre, Donald. The Battle of the Atlantic. 1961. Reprint. Barnsley, South Yorkshire, England: Pen and Sword Books, 2006. Review of antisubmarine warfare during World War II by a former captain of British antisubmarine warfare units. Emphasizes not only the close cooperation between air and sea forces in fighting the U-boats but also the coordination of military men and scientists, who provided the sophisticated electronic equipment that finally gave the Allies an edge.
• Möller, Eberhard, and Werner Brack. The Encyclopedia of U-Boats: From 1904 to the Present. London: Greenhill Books, 2005. Comprehensive reference volume covers the full history of the German U-boat. Includes detailed information on individual boats’ service records, crew strengths, locations, and more.
• Tall, Jeffrey. Submarines and Deep-Sea Vehicles. San Diego, Calif.: Thunder Bay Press, 2002. Illustrated history of submarines includes discussion of Germany’s U-boat fleet.
• Terraine, John. The U-Boat Wars, 1916-1945. New York: G. P. Putnam’s Sons, 1989. Exhaustive study of warfare and tactics in both world wars, laced with detail about individuals, flotillas, strategies, and technology. Highly recommended.

Anschütz-Kaempfe Invents the First Practical Gyrocompass

First German U-Boat Is Launched

World War I

Spain Declares Neutrality in World War I

German Torpedoes Sink the Lusitania

Langevin Develops Active Sonar

Battle of Jutland