The rebels gained the upper hand but Thi was reluctant to push for a complete victory, and the coup was defeated after Diệm falsely promised to make reforms in order to buy time for loyalists to rescue him.

The disquiet escalated into open rebellion by pro-Thi military units, allied to Buddhist anti-junta activists who were calling for civilian government and an end to the US-driven war expansion policy.

The Cao Đài and Hòa Hảo religious sects had their own private armies and de facto states in the Mekong Delta, while the Bình Xuyên organized crime syndicate controlled the national police, had their own military, and dominated the rampant drug trade, prostitution and illegal gambling in the southern capital Saigon.

[8] In October 1955, Diệm deposed Bảo Đại in a fraudulent referendum overseen by his brother Ngô Đình Nhu and declared himself President of the newly proclaimed Republic of Vietnam.

[10][11] The coup was executed ineffectually;[10] although the rebels captured the headquarters of the Joint General Staff at Tan Son Nhut Air Base,[11] they failed to block the roads leading into Saigon and cut off loyalist reinforcements.

[14] The casualties included a large number of anti-Diệm civilians; Thi exhorted them to bring down the Ngô family by charging the palace; 13 were gunned down by the loyalist soldiers as they invaded the grounds.

[21] Soon after arriving home, Thi found himself involved in another coup plot, acting as the link between Khánh and Đỗ Mậu, two generals disgruntled with their position under the military junta of Minh, who oversaw the overthrow of Diệm.

Other notable recruits were Diem loyalist and former chief of the Civil Guard, Duong Ngoc Lam, who was under investigation for corruption, and General Đức, who had recently returned from exile in Paris.

At 03:00, Khánh took over the Joint General Staff Headquarters at Tan Son Nhut, and by dawn, the coup had succeeded without a shot being fired as Minh's junta was caught unaware.

This group of young officers were headlined by Thi, Kỳ, IV Corps commander General Nguyễn Văn Thiệu, and Admiral Chung Tấn Cang, the head of the Republic of Vietnam Navy.

[43][45] Minh and the other aging generals were arrested and flown to Pleiku, a Central Highlands town in a Montagnard area and forcibly retired, while other officers were simply imprisoned in the capital.

The NSC was a new political party active in the I Corps region that opposed the expansion of the war and was aligned with Thi and the Buddhist activist monk Thích Trí Quang.

[47] The deposal prompted US Ambassador Maxwell D. Taylor to angrily berate Thiệu, Thi, Kỳ and Cang in a private meeting and threaten to cut off aid if they did not reverse their decision.

A CIA informant reported that the arguments with Taylor had incensed the volatile Thi so much he privately vowed to "blow up everything" and "kill Phan Khac Suu, Trần Văn Hương and Nguyen Khanh and put an end to all this.

[58] Shortly before noon on 19 February,[59][60] the undetected communist agent,[61] Colonels Thảo and Phát used tanks and some infantry battalions to seize control of the national military headquarters, post office and the radio station of Saigon.

[57] While Kỳ used air power to stop the two sides from confrontation by threatening to bomb them if they opened fire,[67] the Americans consulted with Thi and General Cao Văn Viên, the commander of III Corps surrounding Saigon.

[59][68][69] Early in the morning, Thi, who gained the support of Kỳ, proposed a motion within the junta to remove Khánh and force him into exile, and the final vote was unanimous—Khanh was absent from the meeting.

[59][70] Kỳ, Thi and Thiệu then became the key figures in a junta that continued with Sửu and Prime Minister Phan Huy Quát as a civilian front, although General Minh became the nominal commander-in-chief of the armed forces.

[2] Thi also manoeuvred to have his trusted subordinate Colonel Pham Van Lieu installed as the head of the national police—a body controlled by the army and effectively a military unit—increasing his political power.

Kỳ and Thiệu, both pro-American and supportive of a drastic escalation in anti-communist military activity, became prime minister and head of state respectively, the latter post being largely ceremonial.

[76] Regardless of who held the top jobs, no officer had firm control over his peers, and the respective corps commanders were effectively allowed to independently rule their own regions in return for ongoing support of the junta.

This caused embarrassment to US military officials who felt the introduction of combat troops and resultant American casualties would not be received well by the public when contrasted with Thi's celebratory fanfare.

Soon after the Americans were in position, Thi tipped off Marine Lieutenant General Lewis W. Walt about a major movement of Việt Cộng insurgents near Chu Lai in Quảng Trị Province near the border with North Vietnam.

[79] A large part of the South Vietnamese military was the Regional and Popular Forces, militia that served in their native areas, and they appreciated a commander with whom they had a regionalistic rapport.

[81] The historian Stanley Karnow said of Kỳ and Thi: "Both flamboyant characters who wore gaudy uniforms and sported sinister moustaches, the two young officers had been friends, and their rivalry seemed to typify the personal struggles for power that chronically afflicted South Vietnam.

He said the populace would never support the generals' war effort as long as they lived so comfortably, and he mocked them for ostentatiously flying their wives and mistresses to Hong Kong for shopping expeditions.

[77] The Americans wanted to ease Thi out of the corridors of power by offering him an economic future in the US and free education for his children,[79] and Lodge and Westmoreland personally spoke to him in an attempt to convince him to accept, but they were unsuccessful.

"[1] With the health story exposed as a sham, Kỳ gave a series of reasons for dismissing Thi, accusing him of being too left-wing, ruling I Corps like a warlord, having a mistress who was suspected of being a communist, and being too conspiratorial.

Kỳ knew that Thi supported negotiations with the communists as a means of ending the war, and had a history of consistently removing officials and military figures who promoted such a policy, but did not publicly mention this as a reason.

[88] While the Struggle Movement was finally ebbing away, Thi agreed to meet with Kỳ at an American air base in Chu Lai to reach a settlement, seeing as the junta was going to prevail in any case.