As written; (Wikipedia) From 1954-1975 Vietnam was split into North and South Vietnam. During a 300 day period where the border between the two sides was temporarily open, many North Vietnamese Catholics fled out of fear that they would be persecuted by the Viet Minh. In a country where surveys of the religious composition estimated the Buddhist majority to between 70 and 90 percent, President Ngo Dinh Diem's policies generated claims of religious bias.
As a member of the Catholic minorities, he pursued policies which antagonised and disenfranchised the Buddhist majority. The government was biased towards Catholics in public service and military promotions, and the allocation of land, business favours and tax concessions. Diem once told a high ranking-officer, forgetting the man was from a Buddhist background, "Put your Catholic officers in sensitive places. They can be trusted". Many officers in the Army of Republic of Vietnam converted to Catholicism to better their prospects.
The distribution of firearms to village self-defense militias intended to repel Viet Cong guerrillas saw weapons only given to Catholics. Some Catholic priests ran their own private armies, and in some areas forced conversions occurred. Some villages converted en masse to receive aid or avoid forcibly resettled by Diem's regime. The Catholic Church was the largest land owner in the country, and its holdings were exempt from reform and given extra property acquisition rights, whilst restrictions against Buddhism remained in force. Catholics were also de facto exempt from the corvee labor that the government obliged all citizens to perform; U.S. aid was disproportionately distributed to Catholic majority villages. In 1959, Diem dedicated his country to the Virgin Mary.
The white and gold "Vatican flag" was regularly flown at all major public events in South Vietnam. The newly constructed Hue and Da Lat universities were placed under Catholic authority to foster a Catholic-influenced academic environment.
In May 1963, in the central city of Hue, where Diem's elder brother Pierre Martin Ngo Ding Thuc was archbishop, Buddhists were prohibited from displaying the Buddhist flag during the sacred Buddhist Vesak celebrations. A few days earlier, Catholics were encouraged to fly Christian religious flags at a celebration in honour of Thuc. This led to a protest against the government, which was violently suppressed by Diem's forces, resulting in the killing of nine civilians. This led to a mass campaign against Diem's government during the Buddhist crisis. Diem was later deposed and was assassinated on 2nd November 1963.
Over the years there has been some controversy between the leaders of the Vietnam government and the Vatican even though there has been regular diplomatic discussions and dialogue between the two to ease restrictions on the nominations of bishops in Vietnam and restrictions on Catholic life here due to political issues in the past .
By far the most wide spread Christian church in Vietnam, Roman Catholicism first entered the country through Portuguese Catholic Missionaries in the 16th century and strengthened its influence during French colonial rule. While the earliest missions were only successful at gaining converts, later missions by Jesuit missionaries defiantly saw the definitive establishment of Christian centres within the local population.
Jesuit missionary Alexandre de Rhodes and Antoine Marquez priests from the region of Provence France worked in Vietnam between 1624 to 1644, were perhaps the most notable missionaries and responsible for converting more than 6,000 people.
In the 17th century, de Rhodes created an alphabet for the Vietnamese language using the Latin script using added diacritic marks based on the work of earlier Portuguese missionaries. The system continues to be used today, and is called Quoc Ngu ( literally " national language " )
Long-established religions in Vietnam include the Vietnamese Folk Religion, which has historically structured by the doctrines of Confucianism and Taoism from China, as well as a strong tradition of Buddhism ( called the three teachings or Tam Giao ). Vietnam is one of the least religious countries in the world. According to official statistics from the government, as of 2014 there are 24 million people identified with one of the recognised organised religions, out of a population 90 million people. Of these, 11 million are Buddhists, 6.6 million are Catholics, 4.4 million are Caodaists, 1.4 million are Protestants, 1.3 million are Hoahaoists, and there are 75,000 Muslims, 7,000 Bahais , 1,500 Hindus and other smaller groups. Traditional folk religion ( worship of gods, goddesses and ancestors ) have experienced a rebirth since the 1980s.
According to the estimates by the Pew Research Center, in 2010 most Vietnamese people practice folk religions ( 45.3 percent ), Buddhists constitute 16.4 percent of the population, around 8.2 percent of the Vietnamese are Christians ( mostly Catholics ), and around 30 percent are unaffiliated to any religion. Officially the Socialist Republic of Vietnam is an Atheist State as declared by its Communist Government.