Nguyen Ngoc Tho
Nguyen Ngoc Tho (1908-?) was Vice-President of the Republic of Vietnam (South Vietnam) under Ngo Dinh Diem and the first Prime Minister, for a time after Diem's overthrow in the Vietnam War, Buddhist crisis and military coup of 1963. Of the Buddhist majority rather than Diem's Catholic minority, while he did not command major personal forces, he had important roles in brokering arrangements with the politically powerful Buddhist.
A southern Buddhist, he was born in Long Xuyen province in Cochinchina, and first worked in the French civil service. He had been imprisoned by the French in 1945, and shared a jail cell with Duong Van Minh; they became friends.
In 1954, he became Interior Minister under Bao Dai, and then Diem.
Diem's Vice President
Tho was the highest-ranking Buddhist in the Diem government. As opposed to Diem, who was from Annam, he also gave a regional link to the people of the Mekong Delta. His friendship with Minh also connected him with military circles, at a personal level not shared by Diem.
Tho was assigned, in the fall of 1956, to execute a Diem-initiated program to Vietnamize ethnic Chinese resident in South Vietnam: 1,000,000 Chinese-identified people, especially in the Saigon district of Cholon, dominated much of the economy.  The order barred "foreigners", including Chinese, from 11 kinds of businesses, and demanded the half-million Vietnamese-born men, known as "uncles", "Vietnamize", including changing their names to a Vietnamese form.
Before the Diem overthrow
He was Diem's negotiator with Buddhist activists in 1963. 
It has been suggested he was aware of the coup planning, possibly through his friendhip with Minh. He was on an internal U.S. government list of potential replacements for Diem, written by State Department official Joseph Mendenhall, although it is not clear if he knew he was one of the preferred successors. The list assumed Diem would be replaced by a civilian government.
After the coup
As well as being Prime Minister under the military-controlled Provisional Government, led by Duong Van Minh, he was Minister of Finance and National Economy. During his tenure, he was criticized both for being too aggressive in removing Diem loyalists, and not aggressive enough.
On January 29, 1964, Nguyen Khanh's junta ousted Minh's junta in a quick coup, and disbanded the provisional government; Tho retired.
- "Revolution in the Afternoon", Time, November 8, 1963
- "500,000 Uncles", Time, May 13, 1957
- Gettleman, Marvin E.; Jane Franklin & Marilyn Young et al. (1995), Vietnam and America: A Documented History, Grove Press, p. 218
- Mendenhall, Joseph A. (October 25, 1963), Successor Heads of Government, in Prados, John, JFK and the Diem Coup, vol. George Washington University National Security Archive Electronic Briefing Book No. 101