The Vietnam War lasted from November 1, 1955, to April 30, 1975, spanning nearly 20 years (19 years, 5 months, and 29 days). It was a conflict between North Vietnam and its communist allies against South Vietnam and the United States, with direct U.S. military involvement escalating from 1965 until withdrawal in 1973. The war ended with the fall of South Vietnam to the North in 1975

. In summary:

• Start: November 1, 1955
• End: April 30, 1975
• Duration: Almost 20 years

The war was part of the larger Indochina Wars and a Cold War proxy conflict involving the Soviet Union and China supporting the North, and the U.S. backing the South