 Complete the following phrase:  In 1955, Prime Minister Ngô Đình Diệm held a referendum to decide whether the State of Vietnam would remain a monarchy or become a republic. This referendum was blatantly rigged in favor of a republic. Not only did an implausible 98 vote in favor of deposing Bảo Đại, but over 380,000 more votes were cast than the total number of registered voters; in Saigon, for instance, Diệm was credited with 133 of the vote. Diệm proclaimed himself the president of the newly formed Republic of Vietnam. Despite successes in politics, economics and social change in the first 5 years, Diệm quickly became a dictatorial leader. With the support of the United States government and the CIA, ARVN officers led by General Dương Văn Minh staged a coup and killed him in 1963. The military held a brief interim military government until General Nguyễn Khánh 