War in Vietnam (1954–1959)

The 1954 to 1959 phase of the Vietnam War was the era of the two nations. Coming after the First Indochina War, this period resulted in the military defeat of the French, a 1954 Geneva meeting that partitioned Vietnam into North and South, and the French withdrawal from Vietnam (see First Indochina War), leaving the Republic of Vietnam regime fighting a communist insurgency with USA aid. During this period, North Vietnam recovered from the wounds of war, rebuilt nationally, and accrued to prepare for the anticipated war. In South Vietnam, Ngô Đình Diệm consolidated power and encouraged anti-communism. This period was marked by U.S. support to South Vietnam before Gulf of Tonkin, as well as communist infrastructure-building.

The period ended with major negotiations, but formal discussions had started as early as 1950, with less formal meetings during and immediately after the Second World War. France gave limited autonomy in February 1950, Associated States of Indochina (Vietnam, Laos, and Cambodia) within the French Union. The enabling agreement was signed among the five states on 23 December 1950, and was the prerequisite for direct U.S. aid to Indochina.