South Vietnam was often portrayed as having a Buddhist majority, comprising 70% or more of the population. These figures, reported by foreign journalists, were overestimated, as Westerners commonly mistook
folk religion for Buddhism. The actual number of Buddhists was much smaller, at most about 27%.
Ngo Dinh Diem was regarded by "orthodox" historians as having pursued pro-Catholic policies that antagonized many Buddhists. The government was regarded as being biased towards Catholics in public service and military promotions, as well as the allocation of land and business favors. The "private" status that was imposed on Buddhism by the French, which required official permission to conduct public Buddhist activities, was not repealed by Diệm. The white and gold
Catholic flag was allegedly flown at major public events in South Vietnam. However, portrayals by Western media at the time were severely distorted, as Vietnamese Buddhism in fact flourished under Diệm's First Republic. On May 8, 1963, Diệm's officials invoked a rarely enforced law to prohibit the display of religious flags, forbidding Buddhists from flying their
flag on
Vesak, the birthday of
Gautama Buddha. This caused Buddhist indignation, as Catholic flags had been flown a week earlier at a celebration for Diệm's brother, Archbishop
Ngô Đình Thục. On May 8, in Huế, a crowd of Buddhists protested against the ban on the Buddhist flag. The police and army opened fire and threw grenades at the demonstrators, leaving nine dead. Diệm's denial of responsibility for the incident—he blamed it on the communist Viet Cong—led to more discontent among the Buddhist majority. The incident spurred a protest movement against the
religious discrimination of Diệm's Roman Catholic-dominated regime. The dispute came to be known as the
Buddhist crisis, and it provoked widespread and large-scale civil disobedience. The objective of the protests was to have Decree Number 10 repealed, and to gain religious equality. However, the standoff persisted, and in August, the
ARVN Special Forces of Colonel
Lê Quang Tung, loyal to Diệm's brother and chief adviser
Ngô Đình Nhu, raided temples across the country, killing an estimated hundreds and arresting thousands of Buddhist laypeople and monks. After this, the American government began to turn against Diệm and secretly encouraged a coup. On November 1, Diệm was deposed and he and Nhu were assassinated the next day. After Diệm, South Vietnam went through a period of persistent and serious instability, as multiple coups, as well as other failed uprisings, occurred for 18 months. In September 1964, the Catholic Generals
Lâm Văn Phát and
Dương Văn Đức tried to overthrow Khanh after he had removed them under Buddhist pressure. This failed, but in February 1965, Phat tried again with the help of fellow Catholic, Colonel
Phạm Ngọc Thảo, publicly invoking the memory of Diệm in launching their coup. Phát's second attempt also failed, and the pair went on the run, but the inability of Khánh to secure a decisive victory forced him into exile. In mid-1965, Air Marshal
Nguyễn Cao Kỳ and General
Nguyễn Văn Thiệu took charge as prime minister and figurehead president, respectively, and continuity began to arise. and claiming that Cần Lao members were undermining Kỳ. The Buddhist leader Thích Trí Quang said that "Thi is nominally a Buddhist, but does not really care about religion". The Buddhist activists wanted to end the war through a negotiated settlement with the communists and the departure of the Americans, The historian
Robert Topmiller thought that Kỳ may have seen the article as destabilizing and therefore decided to move against Thi. Thi also manoeuvred to have a trusted subordinate installed as the head of the national police, increasing his political power. 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. But their dispute mirrored more than individual ambition." Both were also known for their colourful red berets. Kỳ's ego was boosted by Johnson's praise, and he left Honolulu believing that the United States would support him if he dismissed Thi. Kỳ mustered the support of eight of the generals on the 10-man junta, meaning that along with his vote, there were nine officers in favour of Thi's removal. The junta put Thi under house arrest pending his departure from the country, and then appointed General
Nguyễn Văn Chuân, the erstwhile commander of 1st Division and a Thi subordinate, as the new I Corps commander. At first, Kỳ said that Thi was leaving the country to receive medical treatment for his nasal passages. General Westmoreland, US Ambassador
Henry Cabot Lodge Jr., and the Defense Secretary
Robert McNamara were supportive of the Kỳ-Thiệu regime and their prosecution of the war against the communists, and they opposed Thi, regarding him as not being firm enough against communism. Meanwhile, in the capital in mid-to-late March, Kỳ took the lead in trying to dampen discontent, meeting Buddhist leaders and promising elections and social reform; however, he also warned that street demonstrations would be suppressed. Kỳ claimed that he allowed Thi to return to his old area of command as a goodwill gesture, to keep central Vietnamese happy, and because he promised Thi a farewell visit before going into exile. However, the supporters of Quang appeared unwilling to wait for Kỳ's schedule, calling for the Constituent Assembly that would draft the new constitution to be chosen from provincial and city councils, where Buddhists did well in elections, but Kỳ refused. While Quang seemed unlikely to see eye-to-eye with Kỳ, the Saigon-based Buddhist leader
Thich Tam Chau appeared open to an accommodation with Kỳ. ==Military threats by Kỳ and ongoing unrest==