Key events in the background to the Vietnam war:
1945 - Viet Minh - a broad front of Vietnamese patriots and nationalists controlled by the Communist Party - seize power. Ho Chi Minh announces independence.
1946 - French forces attack Viet Minh in Haiphong in November sparking the war of resistance against France.
1950 - Democratic Republic of Vietnam is recognised by China and USSR.
1954 - At Geneva Conference Vietnam is split into North and South at the 17th Parallel.
1956 - South Vietnamese President Ngo Dinh Diem begins campaign against political dissidents.
1957 - Beginning of communist insurgency in the South.
1959 - Weapons and men from North Vietnam begin infiltrating the South.
1960 - American aid to Diem increased.
1962 - Number of US military advisors in South Vietnam rises to 12,000.
1963 - Viet Cong, the communist guerrillas operating in South Vietnam, defeat units of ARVN, South Vietnamese Army. President Diem overthrown.
1964 - US destroyer allegedly attacked by North Vietnamese patrol boats. This triggers start of pre-planned American bombing raids on North Vietnam.
1965 - 200,000 American combat troops arrive in South Vietnam.
1966 - US troop numbers in Vietnam rise to 400,000, then to 500,000 the following year.
1968 - Tet Offensive - a combined assault by Viet Cong and North Vietnamese Army on US positions - begins. More than 500 civilians die in My Lai massacre.
1969 - President Nixon draws back US ground troops from Vietnam.
1970 - Nixon's National Security advisor, Henry Kissinger, and Le Duc Tho, for the Hanoi government, start talks in Paris.
1973 - Ceasefire agreement in Paris, US troop pull-out completed by March.
1975 - North Vietnamese troops invade South Vietnam and take control of the whole country after South Vietnamese President Duong Van Minh surrenders.