From the American Civil War through the Vietnam War, the United States fought a series of major conflicts. The Civil War began on April 12, 1861, with the southern bombardment of Fort Sumter after escalating tensions over slavery, states rights, and the election of Abraham Lincoln, and over the next four years it became America's bloodiest conflict, claiming 620,000 lives and causing vast destruction, particularly in the South, before Confederate forces surrendered to General Grant at Appomattox on April 9 and to General Sherman on April 26, 1865. The Spanish-American War, fought from April 21, 1898, to December 10, 1898, followed the destruction of the USS Maine in Havana Harbor, which killed 266 crewmen, and ended within eight months after military victories including Manila and San Juan Hill, bringing freedom for Cuba and United States control of Puerto Rico, Guam, and the Philippines. World War I began in 1914 after the killing of Arch Duke Ferdinand of Austria, and the United States entered on April 6, 1917, as tensions with Germany increased and the sinking of the passenger ship Lusitania pushed the nation into the conflict on the side of England, France, and other allied countries; by the end, the United States suffered 300,000 casualties, including 116,708 killed in action. World War II lasted for the United States from December 7, 1941, to September 2, 1945, after a Japanese attack on Pearl Harbor, Hawaii, brought the nation into a war already being fought against Germany, and by its end 15 to 20 million military personnel had been killed, including 407,326 Americans. The Korean War, from June 25, 1950, to July 27, 1953, was fought to stop the expansion of Communism in the southern half of the Korean peninsula, with American troops committed by President Harry S. Truman and assistance secured from the United Nations for the defense of South Korea; it claimed 33,686 American dead, 157,000 wounded, and 8,100 still unaccounted for. The Vietnam War, from December 22, 1961, to May 7, 1975, grew from fears of Communist takeover and United States support for South Vietnam against the Viet Cong and North Vietnam, and it ended in communist rule while imposing emotional and economic costs on the U.S. beyond the loss of 58,151 American lives.