Lusitania

Lusitania, British passenger ship torpedoed and sunk by a German submarine during World War I, on May 7, 1915. A total of 1,198 people were killed, 128 of them U.S. citizens. The Germans claimed that ammunition was being transported on the ship. The incident aroused popular sentiment in the United States for joining the Allied side in the war.

See also: World War I.