Vietnam War was the longest war in which the United States took part. It began in 1957 and ended in 1975. Vietnam, a small country in Southeast Asia, was divided at the time into the Communist Democratic Republic of Vietnam, commonly called North Vietnam, and the non-Communist Republic of Vietnam, commonly called South Vietnam. North Vietnamese and Communist-trained South Vietnamese rebels sought to overthrow the government of South Vietnam and to eventually reunite the country. The United States and the South Vietnamese army tried to stop them, but failed.
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Gilbert, Marc Jason. "Vietnam War." World Book Student. World Book, 2016. Web. 10 Feb. 2016.
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