May 7 - Vietnamese forces defeat the French at Dien Bien Phu.
July 20 - The Geneva Conference on Indochina declares a demilitarized zone at the 17th parallel.
With U.S. backing, Ngo Dinh Diem organizes the Republic of Vietnam as an independent nation and declares himself president. President Dwight D. Eisenhower sends several hundred U.S. civilian and military advisers to assist Diem.
North Vietnam creates a route along the Cambodian border to supply guerilla forces in South Vietnam. It later becomes known as the Ho Chi Minh Trail.
July 8 - Two U.S. military advisers are killed during a battle, becoming the first American casualties of the war.
The National Liberation Front, also known as the Viet Cong, is founded in South Vietnam.
Feb. 7 - Gen. Paul D. Harkins establishes the U.S. Military Assistance Command in Vietnam with 4,000 U.S. military personnel.
Oct. 2 - Defense Secretary Robert S. McNamara reports to President John F. Kennedy after a trip to Vietnam that ''the major part of the U.S. military task can be completed by the end of 1965.''
Nov. 1 - South Vietnamese President Diem and his brother, Ngo Dinh Nhu, are killed in a military coup led by Maj. General Duong Van Minh, who takes over with a military junta.
May 4 - The United States imposes a trade embargo on North Vietnam.
Aug. 2 and 4 - The U.S. destroyer Maddox reports being fired on by a North Vietnamese torpedo boat in the Gulf of Tonkin off the coast of Vietnam. Some historians question whether the ship was really attacked.
Aug. 5 - President Lyndon B. Johnson orders retaliatory attacks on North Vietnamese gunboats and their home bases.
Aug. 7 - Congress approves the Gulf of Tonkin resolution, giving Johnson the authority to wage war against North Vietnam.
March 2 - The United States begins Operation Rolling Thunder, a bombing offensive aimed at forcing North Vietnam to stop supporting the Viet Cong guerrillas in the south.
March 8 - The 4,000-man 9th Marine Expeditionary Brigade reaches South Vietnam. They are the first combat troops to be deployed in the country.
June 19 - Another military coup in South Vietnam brings Air Marshal Nguyen Cao Ky to power.
June 27 - Gen. William C. Westmoreland launches the first purely offensive operation by American ground forces in Vietnam, sweeping into Viet Cong territory northwest of Saigon.
April 24 - American attacks on North Vietnam's airfields begin. The attacks inflict heavy damage on runways and installations. By the end of the year, all but one of the north's MiG bases has been hit.
May - Desperate air battles rage in the skies over Hanoi and Haiphong. American air forces shoot down 26 North Vietnamese jets, decreasing the north's pilot strength by half.
July 1 - Ky withdraws as a candidate for president of South Vietnam and agrees to run for vice president on a ticket headed by Nguyen Van Thieu.
Sept. 3 - Thieu and Ky are elected.
Jan. 30 - The Tet offensive is launched, with 70,000 North Vietnamese and Viet Cong troops attacking more than 100 cities and towns in South Vietnam. Although the offensive is a military failure for the north, the loss of 2,500 Americans is a serious blow to domestic support for the war.
March 16 - Soldiers with U.S. Charlie Company round up and kill hundreds of civilians in the hamlet of My Lai. Lt. William L. Calley is eventually convicted of premeditated murder in the My Lai massacre and serves three years under house arrest.
March 31 - In a nationally televised speech, Johnson shocks the nation by saying he will not run for another term as president. He earlier announces a bombing halt over much of North Vietnam in an effort to induce the North Vietnamese into peace talks.
February - President Richard M. Nixon authorizes the bombing of North Vietnamese and Viet Cong bases in Cambodia. Over the next four years, U.S. forces drop more than a half million tons of bombs on Cambodia.
April - U.S. combat deaths in Vietnam exceed the 33,629 men killed in the Korean War.
June 7 - After meeting with Thieu at Midway, Nixon announces that 250,000 U.S. troops will be withdrawn in a plan to turn the war effort over to the South Vietnamese. The policy is known as the ''Vietnamization'' of the war.
Sept. 3 - Ho Chi Minh, who led North Vietnam against both the French and the Americans, dies.
Nov. 15 - The Vietnam War Moratorium demonstration draws 600,000 people to Washington, D.C.
April 30 - U.S. and South Vietnamese troops invade Cambodia in what Nixon says is a bid to save American lives and destroy Communist bases and supply lines supporting the war in Vietnam.
May 4 - Four students are killed by National Guardsmen during an anti-war protest at Kent State University in Ohio.
Jan. 13 - Nixon announces a reduction of 70,000 U.S. troops by May 1. Combined with previous withdrawals, this leaves U.S. strength in Vietnam at 69,000, the lowest level in nearly seven years.
March 30 - More than 20,000 North Vietnamese troops cross the DMZ, forcing the South Vietnamese units into a chaotic retreat.
June 17 - U.S. ground combat ends in Vietnam; a residual force of fewer than 60,000 advisers, technicians, and helicopter crews remains.
Dec. 18 - Nixon orders a new bombing campaign against North Vietnam. U.S. aircraft drop more than 20,000 tons of bombs in the 12-day operation.
Jan. 27 - United States, North Vietnam, South Vietnam and the Viet Cong sign a peace agreement in Paris calling for the withdrawal of the remaining U.S. forces and the release of all American POWs by April 1.
The U.S. military draft ends.
Feb. 12 - The first American POWs are released.
March 29 - The last U.S. combat troops leave Vietnam.
Aug. 15- The American pullout is complete when U.S. warplanes cease bombing missions in Indochina.
March - North Vietnam sends 100,000 soldiers against the major cities of South Vietnam.
March 11 - North Vietnamese forces rout South Vietnamese troops from the provincial capital of Buon Ma Thuot, the southern anchor of Saigon's defenses in the Central Highlands. South Vietnamese forces disintegrate in panic.
March 25 - Hue, South Vietnam's third largest city, falls to the North Vietnamese.
March 29 - North Vietnam captures Danang, the largest military base north of Saigon.
April 21 - President Nguyen Van Thieu resigns in an unsuccessful 11th-hour bid for a settlement. He accuses the United States of having ''led the South Vietnamese people to death.''
April 29 - As communist forces close in on Saigon, U.S. helicopters begin evacuating Americans and South Vietnamese from the rooftop of the U.S. Embassy. In 18 hours, more than 1,000 American civilians and nearly 7,000 South Vietnamese refugees are flown out of Saigon.
April 30 - 4:03 a.m. - Two U.S. Marines are killed in a rocket attack at Saigon's Tan Son Nhut airport. They are the last Americans to die in the war.
April 30 - 7:52 a.m. - The last helicopter lifts off from the roof of the U.S. Embassy, ending a mass evacuation of Americans and South Vietnamese.
April 30 - 10:28 a.m. - The last leader of South Vietnam, Gen. Duong Van Minh, announces on radio that the nation has surrendered.
April 30 - 12:45 p.m. - Nguyen Trung Kien, a 20-year-old female guerrilla, raises the flag of the Viet Cong's provisional revolutionary government over the presidential palace in Saigon.