Tôn Thất Đính, Vietnamese general (d. 2013)

Lieutenant General Tôn Thất Đính (November 20, 1926 – November 21, 2013) was an officer who served in the Army of the Republic of Vietnam (ARVN). He is best known as one of the key figures in the November 1963 coup that led to the arrest and assassination of Ngô Đình Diệm, the first president of the Republic of Vietnam, commonly known as South Vietnam.

A favorite of the ruling Ngô family, Đính received rapid promotions ahead of officers who were regarded as more capable. He converted to Roman Catholicism to curry favor with Diệm and headed the military wing of the Cần Lao party, a secret Catholic organization that maintained the Ngôs' grip on power. At the age of 32, Đính became the youngest ever ARVN general and the commander of the II Corps, but he was regarded as a dangerous, egotistical, and impetuous figure with a weakness for alcohol and partying.

In 1962, Đính, whom Diệm regarded as one of his most loyal officers, was appointed commander of the III Corps that oversaw the region surrounding the capital Saigon, making him important to the prospects of any coup. In late 1963, as Diệm became increasingly unpopular, Đính's colleagues recruited him into a coup plot by playing on his ego and pitting him against Diệm. Diệm and his brother and chief advisor Ngô Đình Nhu were aware of the plot but did not know of Đính's involvement. Nhu planned a fake coup of his own in an attempt to trap his opponents and strengthen the family's regime. Đính was placed in charge of the fake coup and sabotaged it. On November 1 the rebels' actual coup proceeded and the Ngô brothers were deposed and executed.

After the coup, Đính became one of the 12 members of the Military Revolutionary Council (MRC), but this lasted only three months before a bloodless coup by General Nguyễn Khánh. Đính and his colleagues were put under house arrest by Khánh and falsely accused of promoting a neutralist plot. The subsequent military trial collapsed. The generals were convicted of "lax morality", but were eventually allowed to resume their military service, albeit in meaningless desk jobs. Following Khánh's exile by another group of generals, Đính was appointed to command the I Corps in 1966 and ordered to put down the Buddhist Uprising, but Prime Minister Nguyễn Cao Kỳ disapproved of his conciliatory policies. Kỳ launched a successful surprise attack against Đính, who fled, but was later captured and briefly imprisoned by Kỳ. After his release, Đính worked in the media and was elected to the Senate in 1967. He served in the upper house until the fall of Saigon in April 1975, when he fled Vietnam.