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 favourite 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 favour 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, which 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 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.

Early years Đính was born in the central highlands resort town of Da Lat on November 20, 1926, into the Tôn Thất family of Huế, who were relatives of the Nguyễn dynasty. In 1943, he took a clerical job at Da Lat Court. He enlisted in the Vietnamese National Army (VNA) of the French-backed State of Vietnam at Phu Bai in 1949 and was first trained as a non-commissioned officer at Mang Cá, Huế, before being accepted into the first intake of the Huế Military Academy. After one year of training, he was commissioned as a lieutenant. He then trained as a paratrooper and attended the Saumur Cavalry School in France.Sheehan, p. 356. As a captain, he was made the commanding officer of the VNA's Mobile Task Force (GM 2) in Ninh Giang in northern Vietnam. After graduating at the top of a Military Staff Training Course in Hanoi, he was promoted to the rank of major and put in command of the forces in Duyên Hải, in the northern coastal province of Thái Bình, as a battalion commander. In 1952, he was made a lieutenant colonel and appointed to command the 31st Tactical Group (GM 31), based in the province of Hải Dương but also covering the adjoining provinces of Nam Định and Ninh Bình. He was the Deputy Commander of Operations for Colonel Paul Vanuxem when the VNA and French Far East Expeditionary Corps withdrew from Ninh Bình to Tuy Hòa on the South Central Coast as part of Operation Auvergn following the partition of Vietnam.

He became a protégé of Ngô Đình Cẩn, a younger brother of Prime Minister Diệm. Cẩn, who unofficially controlled the region of central Vietnam near Huế, was impressed by what he considered to be an abundance of courage on the part of Đính. Within six years of enlisting in the military, Đính had risen to the rank of colonel and was made the inaugural commander of the newly formed 32nd Division based in Da Nang in the centre of the country on January 1, 1955. Đính led the unit until November 1956, when it was renamed the 2nd Division.Tucker, pp. 526–533.

Diệm deposed head of state Bảo Đại in a fraudulent referendum in 1955 and proclaimed himself president of the newly created Republic of Vietnam, commonly known as South Vietnam.Jacobs, pp. 86–89. The VNA thus became the Army of the Republic of Vietnam (ARVN). Born into a nominally Buddhist family, Đính had converted to Catholicism in the hope of advancing his career. The change in religion was widely perceived as a factor in his rapid promotion over more capable officers. A devout member of the Catholic minority, Diệm dedicated the country to the Virgin Mary and heavily disenfranchised and disadvantaged the Buddhist majority.Jacobs, pp. 88–95.

Đính once described himself as "fearless and arrogant" and Diệm's adopted son;Wright, p. 40. the president was a lifelong bachelor.Jacobs, p. 19. In August 1957, he was appointed commander of the 1st Division based in Huế, the old imperial capital and Cần's base. Đính served there for one year, until he became a one-star general and received a wider-reaching command in August 1958,Karnow, pp. 307–322. making him the youngest-ever ARVN general.Tucker, pp. 288–289. Đính's favour among the Ngô family saw him appointed in 1958 to head the military wing of the Cần Lao, the secret organisation of Vietnamese Catholics loyal to the Ngô family that maintained the family's grip on power.

Despite the high regard the Ngô family held him in, Đính had a poor reputation among his colleagues. Regarded by his peers as ambitious, vain and impulsive, he was known mainly for heavy drinking in Saigon's nightclubs,Jacobs, p. 169. and the Central Intelligence Agency labelled him a "basic opportunist".Prochnau, pp. 442–443. He was known for always wearing a paratrooper's uniform with a red beret at a steep angle, and being accompanied by a tall, uncommunicative Cambodian bodyguard.Jones, p. 397. Senior Australian Army officer Ted Serong, who worked with Đính, called him "a young punk with a gun – and dangerous".Blair (2001), p. 56.

Xá Lợi Pagoda

In August 1958, Đính was made the commander of the II Corps, which oversaw the Central Highlands region, mainly inhabited by indigenous tribes. He was based in the mountainous town of Pleiku and oversaw the surrounding region and the lowlands to the north of the capital of Saigon.Hickey, pp. 100–101. This put him in control of the 5th, 22nd, and 23rd Divisions, one-third of the divisions in the country. At the time, the CIA had been training Montagnard tribesmen under the Village Defense Program (later to become the Civilian Irregular Defense Group) with the stated intention of resisting communist infiltration, but Đính regarded it as an attempt to divide and conquer and undermine him. He estimated that 18,000 tribesmen had been armed,Blair (2001), p. 62. and said to Ngô Đình Nhu – one of Diệm's younger brothers and his chief adviser – that "the Americans have put an army at my back". CIA officer Lucien Conein admitted years afterwards that Đính's claim was correct; that Nhu and Diệm had no previous idea of what the Americans had been doing.Catton, p. 155. Đính wrote to Diệm to complain that his units were being weakened by the policy of promoting officers for political reasons,Toczek, p. 45. despite having been a beneficiary himself of this non-merit-based policy.

The reorganisation of the corps boundaries in December 1962 created a fourth region. The entire region surrounding the capital, Saigon, came under the purview of the III Corps, whereas the previous arrangement saw two corps controlling the regions to the north and south of the capital. As a key supporter of Diệm, Đính was named commander of the III Corps because the Ngô family trusted him to defend them in the face of any coup attempts. Under the III Corps were the 5th and 25th Divisions, located in Biên Hòa and Cu Chi, on the north-eastern and north-western outskirts of Saigon, respectively.

In August 1963, Nhu, who controlled the special forces and secret police, allowed Đính to have a hand in planning raids against Buddhist dissidents who had been organising at the Xá Lợi pagoda,Halberstam, p. 181. Saigon's largest.Karnow, p. 301. The raids involved the deployment of the 5th Division into the capital.Blair (2001), p. 59. Although the execution of the raids – which left hundreds dead – was primarily the responsibility of Colonel Lê Quang Tung, the special forces head,Halberstam, p. 145. Đính privately took responsibility, stating to a journalist, "I have defeated Henry Cabot Lodge [the US ambassador to South Vietnam]. He came here to stage a coup d'etat, but I, Tôn Thất Đính, have conquered him and saved the country."Halberstam, p. 147. In the aftermath of the raids, Foreign Minister Vũ Văn Mẫu resigned in protest, shaved his head like a monk, and sought to leave on a pilgrimage to India; Nhu ordered Đính to jail him. At the urging of another general, Đính put Mẫu under house arrest instead.Sheehan, p. 357.

During this period, Đính told a dinner guest that he had the pleasure of dining with a great national hero. When the guest asked Đính where the hero was, Đính said "it is me" and claimed to have defeated the Americans. Đính's ego had been played upon by the Ngô brothers, who had themselves reiterated this point and paid him a large cash bonus after the pagoda raids.Sheehan, pp. 356–357. In the heady times after the attacks, Đính had a "somewhat incoherent" debate with his American advisor, claiming "he [Đính] was without doubt the greatest general officer in the ARVN, the saviour of Saigon [...] and soon he would be the top military man in the country."Catton, p. 203. In a press conference after the raids, Đính claimed to have saved South Vietnam from Buddhists, communists and "foreign adventurers", a euphemism for the United States.

After being questioned sharply, Đính quickly became angry. Ray Herndon of United Press International asked him to name the country that he was referring to, but Đính dodged the question. Herndon lampooned him by saying that a national hero should be able to identify the national enemy, and asked him to call Madame Nhu, the de facto First Lady known for her anti-American comments, to get help in identifying the hostile country in question. After several reporters derisively laughed at these comments, Đính stormed out of the conference.Halberstam, p. 182.

Defection and coup