Christianity was first introduced to Vietnam  in 16th century and established a solid position in Vietnamese society since 17-18th centuries. At present Vietnam has the fourth-largest Roman Catholic population in Asia, after the Philippines, India and possibly the People's Republic of China. Roman Catholics and Protestants today constitute 7% and 1% of the country population accordingly; the newest census of Government shows that is 8% (7% Catholic and 1% Protestant) . Christian communes still remain under control of state authorities . Foreign missionaries legally are not allowed to proselytize or perform religious activities without government approval. Undeclared missionaries from several countries are active in Vietnam.
The most active introducers of Western enlightenment were the Jesuits, who were, at that time, in the prime of their exploratory efforts. The Franciscans, Dominicans, and others, although prominent, never reached the influence of the Jesuits who were determined to plant the spiritual and cultural power of Roman Catholic Church in Southeast Asia. Having arrived there about 1627, they developed their activities in many fields. Their activities were helped by the printing of the first Bible in 1651, and the growing influence of several individuals, who were welcomed in certain powerful circles. Jesuit missionary Alexandre De Rhodes created in 17th century a written system of Vietnamese language largely using the Roman alphabet - it is used today and now called Quốc Ngữ (national language).
After the end of the French rule and Vietnam division in mid-1950s, Catholicism declined in the North, where the communists regarded it as a reactionary force opposed to national liberation and social progress. In the South, by contrast, Catholicism was expanded under the presidency of Ngo Dinh Diem, who promoted it as an important bulwark against North Vietnam. Diem gave extra rights to the Catholic Church and preferentially promoted Catholic military officers while restricting Buddhism. In 1955 approximately 600,000 Catholics remained in the North after an estimated 650,000 had fled to the South.
In 1975 the Communist authorities, which united the country by military force and after the US troops withdrawal, claimed that the religious activities of Roman Catholics were stabilized and that there was no religious persecution. Meanwhile, the Government acted to isolate and to neutralize hard-core opposition within local Catholics to party policy and to persuade less strongly opposed factions to join a party-controlled "renovation and reconciliation" movement. A significant number of Vietnamese Roman Catholics, however, remained opposed to communist authority.
Roman Catholic dioceses
There are 26 dioceses including three archdioceses. The Archdioceses are:
- Archdiocese (Metropolitan) of Hanoi
- Archdiocese (Metropolitan) of Hue
- Archdiocese (Metropolitan) of Ho Chi Minh city, (former Saigon). 
The dioceses are:
- Diocese of Ba Ria
- Diocese of Bac Ninh
- Diocese of Ban Mê Thuôt
- Diocese of Bùi Chu
- Diocese of Cân Tho
- Diocese of Ðà Lat
- Diocese of Ðà Nang
- Diocese of Hai Phòng
- Diocese of Hung Hóa
- Diocese of Kontum
- Diocese of Lang Son and Cao Bang
- Diocese of Long Xuyên
- Diocese of My Tho
- Diocese of Nha Trang
- Diocese of Phan Thiêt
- Diocese of Phát Diêm
- Diocese of Phú Cuong
- Diocese of Quy Nhon
- Diocese of Thai Binh
- Diocese of Thanh Hóa
- Diocese of Vinh
- Diocese of Vinh Long
- Diocese of Xuân Lôc
Protestantism was introduced in 1911 at Da Nang by the Canadian missionary Robert A. Jaffray. As part of the Christian Missionary Alliance, over 100 missionaries were sent to Vietnam, assisting the faith's growth in the country.
By 1967 information, Protestant communities were represented mainly within South Vietnam. Those communities included the French Reformed Church, Anglican-Episcopalian[disambiguation needed], Christian and Missionary Alliance, Baptists, Church of Christ, Worldwide Evangelization Crusade, and Seventh-day Adventists. Other Protestant associations were also represented in some social services and welfare agencies. In 1967 there were 150,000 Protestant adherents in South Vietnam, representing about 1% of the total population.
Protestant communes in the North decreased in membership to about 1,200 by the end of the Vietnam war. Several Protestant church properties were confiscated during the communist takeover of South Vietnam in 1975.
Present estimates of the number of Protestants range from the official government figure of 500,000 to claims by churches of 1,600,000 or more. The two officially recognized Protestant churches are the Southern Evangelical Church of Vietnam (SECV), recognized in 2001, and the smaller Evangelical Church of Vietnam North (ECVN), recognized since 1963. The SECV had affiliated churches in the southern provinces of the country. By some estimates, the growth of Protestant believers in Vietnam has been as much as 600 percent over the past ten years. Some of the new converts belong to unregistered evangelical house churches. Based on believers' estimates, two-thirds of Protestants were members of ethnic minorities, including Hmong, Dzao, Thai, and other minority groups in the Northwest Highlands, and members of ethnic minority groups of the Central Highlands (Ede, Jarai, Bahnar, and Koho, among others). 
Nowadays at least 50 % of the Protestant population are tribal people.  Particlularly Hmong and Hre tribals suffer from persecution of Christians.  By May, 2006, over 300 Montagnard people remained in Vietnamese prisons for their faith.A young Hroi (ethnic minority) man who refused to reject his Christian faith reportedly died from injuries received under official interrogation in April 2007. By the 2008 estimates of Release International, many Christians from Vietnam’s tribal highlands are still regarded as enemies and targeted as "agents of America". They are reportedly beaten, tortured and starved behind bars, despite the official claims and guarantees for freedom of religion.
Mennonite and Baptist movements were officially recognized by Hanoi in October, 2007, which was estimated as some improvement of religious freedom in the country. Pastor Nguyen Quang Trung, provisional president of the Vietnam Mennonite Church, taking part in the official ceremony of the above authorisation, quoted his Church’s motto: "Living the Gospel, worshipping God, and serving the nation." .
Bible translations in Vietnamese
Although the modern Vietnamese alphabet was created in the 17th century by Jesuit missionary Alexandre De Rhodes, the first Bible books translated for common use into Vietnamese appeared only in 1872. In 1963 the Bible in Vietnamese was published by the Roman Catholic Church.
The organized work of United Bible Societies in Vietnam began in 1890. In 1966 the Vietnamese Bible Society was established. The Bible societies distributed 53,170 Bible examples and 120,170 New Testament examples in Vietnamese within the country in 2005.
Eastern Orthodox Christianity
- Vietnamese Martyrs
- Roman Catholicism in Vietnam
- Protestants in Vietnam
- Mennonite Church in Vietnam
- Marian Days
- Nguyen Van Thuan
- ↑ 1.0 1.1 Open Doors International : Vietnam
- ↑ 
- ↑ Vietnam Affirms Consistent Policy on Religion: White Paper
- ↑ 4.0 4.1 US State Department Country Report 2006 on Vietnam
- ↑ 
- ↑ Catholic Forum
- ↑ "Catholic Dioceses in Vietnam". Giga-Catholic Information. 2007-05-10. http://www.gcatholic.com/dioceses/data/countryVN.htm. Retrieved 2007-05-15.
- ↑ GCatholic Directory
- ↑ Protestantism in South Vietnam, US Navy, Bureau of Naval Personnel, Chaplains Division, 1967
- ↑ Vietnam
- ↑ Open Doors International : The Church in Vietnam
- ↑ Montagnard Foundation
- ↑ BosNewsLife News Center
- ↑ Christian Today Magazine
- ↑ 15.0 15.1 Hanoi officially recognises Baptists and Mennonites, AsiaNews
- ↑ History of the Vietnamese Bible
- ↑ Bible Society work in Vietnam
- ↑ Russian Orthodox Portal, in Russian
- Hudson Institute. "Vietnam Steps up Persecution of Hmong Christians". Center for Religious Freedom. 2005. 
- Montagnard Foundation press release, 2006. RELIGIOUS PERSECUTION CONTINUES IN VIETNAM AS DEGAR CHRISTIANS ARE TORTURED FOR THEIR FAITH 
- Christianity with an Asian Face: Asian-American Theology in the Making. By Peter C. Phan. Maryknoll, N.Y.: Orbis Books, 2003. xvii + 253 pp.
- Report on Vietnam by International Christian Concern 
- Christian persecution in Vietnam. Report by CSW 
- The Catholic Church in Vietnam by Giga-Catholic Information
- Vatican Delegation Goes to Vietnam AP article regarding diplomatic meetings
- Vietnamese Catholic Network in Vietnamese
- Vietnamese Catholic Links
- "Report on Vietnam" by International Christian Concern
- Vietnamese Bible
- The History of Vietnamese Bible Translation
- Jesuit Service in Vietnam
- A New Day in Vietnam, Christianity Today Magazine