Ngô Đình Diệm rose from a Catholic elite family to become South Vietnam’s first president in 1955. Backed by U.S. support, he built an authoritarian regime marked by corruption, religious repression, and authoritarian rule. His refusal to compromise with Buddhists and critics led to unrest and ultimately his assassination in 1963. This video examines his leadership, his downfall, and the chaos that followed in South Vietnam, fueling America’s deeper involvement in the war.