Chronology of the Vietnam War

February 1950 : President Harry Truman sends first 35 advisers to help troops fighting Ho Chi Minh's Communist-led Viet Minh.

1954 : Vietnam divided along 17th parallel; French stronghold at Dien Bien Phu falls.

January 1955 : President Dwight Eisenhower sends U.S. forces to train South Vietnamese.

May 1961 : President John Kennedy sends 400 Special Forces, 100 other advisers.

January 1962 : To expose jungle roads and trails used by Viet Cong, United States begins using an estimated 19 million gallons of a toxic defoliating herbicide.

November 1963 : South Vietnamese President Ngo Dinh Diem assassinated; coups follow.

August 1964 : Major U.S. commitment begins after report that American destroyers are attacked in Gulf of Tonkin; Congress grants president broad powers.

February 1965 : President Lyndon Johnson orders continuous bombing over North Vietnam to force talks.

June 8, 1965 : U.S. commanders authorized to send 23,000 advisers to combat.

November 1965 : Battle of la Drang Valley, first major encounter between U.S. and North Vietnamese regulars.

June 29, 1966 : Bombing of Hanoi and Haiphong starts

May 1967 : Gen. William Westmoreland seeks more troops. Domestic debate over war intensifies.

Jan. 30, 1968 : Tet Offensive begins. Heavy casualties as North Vietnamese and Viet Cong attack South's seven largest cities and 30 provincial capitals. Ultimately a military defeat for the North but a psychological and political defeat for United States.

March 31, 1968 : Johnson halts bombing over 90 percent of North, asks Hanoi for peaceful solution.

April 1968 : 50,000 U.S. and South Vietnamese troops lift a 76-day siege of the Marine base at Khe Sanh.

Jan. 18, 1969 : Paris peace talks begin.

July 8, 1969 : Troop withdrawal begins. President Richard Nixon later announces "Vietnamization" policy of transferring the fighting to South Vietnamese forces.

Jan. 25, 1972 : Nixon reveals secret peace talks have been going on for months.

March 1972 : North begins months-long " Easter Offensive."

Dec. 18, 1972 : After talks break down, Nixon orders heaviest bombing of the war.

Jan. 8, 1973 : Talks resume; formal pact signed in Paris later that month.

August 1973 : Last American units leave. Fighting continues between South Vietnam and the Viet Cong and North Vietnamese.

1974 : South begins abandoning distant outposts it can no longer defend.

January 1975 : Communist offensive begins.

April 30, 1975 : South Vietnamese government surrenders.