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War Letters | Timeline

U.S. Military Actions and Wars, 1775 - 1994

Signing the Declaration of Independence. Library of Congress.

1775-1783: The Thirteen Colonies
Colonists wage and win a guerilla war for American independence from England.

1798-1800: The Quasi-War
Along the U.S. Atlantic Coast and the West Indies, an undeclared war with France begins; the U.S. wins 9 of 10 naval encounters.

1801-1805: Tripolitan War
Tripoli (now Libya) declares war on the U.S.; the U.S. responds by blockading and then invading Tripoli.

1811: The "Indian Belt" Affair
Across Indiana and Michigan, U.S. forces, led by Tecumseh defeat Native Americans and burn a city, Prophetstown.

1812-1815: The War of 1812
The U.S. wars with Great Britain over freedom of the seas, capture of seamen, and a blockade of U.S. ports. Battles were fought in and around Lake Erie; New Orleans, Louisiana; and the nation's capital.  

1817-1818: First Seminole War
Following Native American raids in Florida, U.S. forces destroy Seminole villages and break tribal resistance.

1832: Assault on Sumatra
In the first U.S. armed intervention in Asia, the U.S. retaliates against an attack on a U.S. merchant vessel, killing 100 Sumatrans and burning the town of Quallah Battoo, located in what is now Indonesia.

1832: Black Hawk War
In Illinois and Wisconsin, Sac and Fox tribes under Sac leader Black Hawk attack white settlers, but are defeated at the Battle of Bad Axe.

1835-1836: Texas Revolution
Texas settlers revolt against Mexico.

1835-1842: Second Seminole War
In Florida, American troops clash with Native Americans led by Osceola; the Seminole people are reduced to 350 in number by 1842.

1838-1839: Aroostook War
The U.S. fights an undeclared war with England over Maine's boundaries. Approximately 10,000 troops camp along the Aroostook River in a conflict without casualties.

1846-1848: The Mexican War
The U.S. declares war against Mexico; the war ends with Mexico ceding all rights to Texas, and the U.S. purchase of New Mexico and California.

1847-1850: Cayuse War
In Washington state, Cayuse destroy the intrusive mission of Marcus Whitman, blaming the missionaries for a smallpox outbreak. In addition to Whitman, his wife, and their helpers, 14 Native Americans are killed. The U.S. military forces the Cayuse to surrender and hangs five people.

1855-1858: Third Seminole War
Brigadier General William S. Harney subdues Billy Bowlegs and other Seminole warriors in Florida.

1856: Bleeding Kansas
Conflict erupts in Kansas between pro- and anti-slavery forces, including John Brown; federal troops quell the fighting.

1857-1858: Mormon Expedition
The U.S. Army subdues Mormons who refuse to obey federal law in Utah.

1861-1865: American Civil War
Americans go to war over slavery and the attempted secession of southern states from the United States.

1871: War with Korea
After merchants are killed in Korea, the U.S. kills 250 Koreans in battle; a treaty is secured in 1882.

1871-1876: Apache Wars
Apache leaders Geronimo and Victorio raid white settlers and soldiers in Arizona; Geronimo surrenders in 1886.

1872-1873: Modoc War
In California and Oregon, U.S. cavalry fight to return the Modoc people and their leader, Kintpuash (known to whites as Captain Jack), to an Oregon reservation; Kintpuash is hanged and the Modoc are exiled to Oklahoma.

1876-1877: Black Hills War
Gold in South Dakota brings in whites to Sioux land. Colonel George A. Custer and 264 soldiers are killed at Little Nighorn; subsequently, the U.S. Army destroys Indian resistance.

1877: Nez Percé War
Across Idaho, Oregon, and the Washington border, the U.S. moves against the previously peaceful Nez Percé people in the Northwest; Chief Joseph leads a skillful retreat towards Canada, but is caught.

1878: Bannock War
Native Americans of the Bannock tribe attack white settlers in Idaho before they suffer heavy losses and are forced back to Fort Hall Reservation.

1890: Messiah War
The U.S. apprehends Sioux leader Sitting Bull, who is killed when followers try to free him. The Sioux surrender but are massacred at Wounded Knee in South Dakota, in this final fight between Native Americans and the U.S. Army.

1893: Coup in Hawaii
U.S. Marines land in the kingdom of Hawaii to aid the overthrow of Queen Lili'upkalani.

1898-1902: Spanish-American War
U.S. victories against Spain lead to the Treaty of Paris, which establishes the independence of Cuba, and cedes Puerto Rico and Guam to the U.S.. The U.S. also purchases the Philippines for $20 million.

1912: Occupation of Nicaragua
Marines arrive in Nicaragua to bolster the government of Adolfo Diaz; the last marines depart in 1934.

1914: Tampico Affair
After U.S. Marines are arrested at Tampico, U.S. forces bombard Veracruz, Mexico, and occupy the city.

1915: Invasion of Haiti
U.S. Marines occupy Haiti after a civil war; a treaty between the U.S. and the Haitian Senate makes the island nation a virtual U.S. protectorate. Troops withdraw in 1934.

1916-1917: Expedition Against Villa
The U.S. military invades Northern Mexico to capture Mexican Pancho Villa, who had raided New Mexico, killing 18; U.S. forces numbering 11,000 withdraw, unable to capture Villa.

1917-1918: World War I
The U.S. ends three years of neutrality in the European conflict, declaring war on Germany. An armistice is declared November 11, 1918.

1918-1920: Siberian Expedition
The U.S. and other Allied troops invade Russia to protect war supplies during the Russian Revolution.

1927: Protection of Shanghai's International Settlement
One hundred Marines land in Shanghai to defend U.S. property during a civil war there.

1941-1945: World War II
The U.S. enters World War II after Japanese planes attack Pearl Harbor in Hawaii; in 1945, Germany and Japan surrender to Allied forces.

1950-1953: Korean War
The U.S. battles North Korean soldiers and then Chinese soldiers in Korea before an armistice is signed in 1953.

1955: Defense of Chinese Nationalists
The U.S. 7th Fleet helps Nationalist Chinese evacuate 25,000 troops and 17,000 civilians from China to Taiwan to escape victorious Communist forces.

1955-1973: Vietnam War
In 1955, U.S. advisers are sent to Vietnam; in 1964 Congress authorizes President Lyndon B. Johnson to "repel any armed attack" in the Gulf of Tonkin Resolution. A cease-fire is declared in 1973.

1961: Bay of Pigs Invasion
A CIA-backed invasion of Cuba fails.

1962: Anti-Communist Intervention
President John F. Kennedy orders 5,000 troops to Thailand to support the right-wing Laotian government.

1965: Dominican Crisis
Marines invade the Dominican Republic at the start of a civil war; troops withdraw in 1966.

1975: Mayaguez Incident
A U.S. merchant ship is rescued from Cambodians by U.S. Navy and Marines off the coast of Cambodia.

1980: Operation Eagle Claw
A military mission to free American hostages in Iran fails.

1983: Operation Urgent Fury
U.S. Marines and Rangers remove U.S. medical students from Grenada.

1986: Operation El Dorado Canyon
U.S. war planes strike Libya in retaliation for the Libyan bombing of a West Berlin disco.

1990-1991: Persian Gulf War
The U.S. leads a multi-nation coalition against Iraq after that country invades Kuwait; Iraq surrenders.

1992-1993: Operation Restore Hope
U.S. troops go to Somalia to help restore order and deliver food during a period of unrest and famine.

1994-1995: Operation Uphold Democracy
The U.S. Army sends troops to Haiti in September 1994 to help restore a democratic government.

1994-1995: Bosnian War
The United States bombs Bosnia to prevent "ethnic cleansing" by Serbs in that region and then sends troops to Bosnia to join a NATO peacekeeping force there, as well as in other Balkan areas including Macedonia and Kosovo.

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