About 68% of all Laotians are Lao-Loum, or lowland Lao, a people related to the people of Thailand; thought to have migrated to Laos from southwestern China in the 8th century, the LaoLoum are concentrated in the lowlands along the Mekong. On the hillsides live the Lao-Theung, or slope dwellers, a diverse group dominated by the Lao-Tai (with various subgroups, including the Black Tai), who are ethnically related to the Lao-Loum. they account for 22% of the population. At higher altitudes are the LaoSoung, or mountain dwellers, a diverse group of ethnic minorities of mainly Malayo-Polynesian or proto-Malay backgrounds. they constitute 9% of the population.
Important among the Lao-Soung, and more prosperous than most Lao because of the opium poppies they grow, are the Hmong (Meo), a people of Tibeto-Burman origin who supported the American presence until 1975 and, because of their continuing insurgency, became the targets of harassment by government and Vietnamese troops. Other important upland tribes, all with customs and religions considerably different from those of the lowland Lao, are the Ho, Kha, Kho and Yao (Mien). Ethnic Vietnamese and Chinese account for 1% of the population.
Lao, the official language and the language of the ethnic Lao, is closely related to the language of Thailand. It is monosyllabic and tonal and contains words borrowed from Sanskrit, Pali and Farsi. Pali, a Sanskritic language, is used among the Buddhist priesthood.
Other groups speak the Tibeto-Burman, Non-Khmer, or Miao-Yao languages. French, formerly the principal language of government and higher education, has been largely replaced by Lao. English and various ethnic languages are also spoken.
Theravada Buddhism is practiced by most of the Lao-Loum, whose daily life is shaped by its rituals and precepts. Buddhist temples, found in every village, town, and city, serve as intellectual as well as religious centers. Vientiane and Luangprabang have been called cities of thousands of temples. More than 70 pagodas were built in Vientiane alone in the 16th century, including the famous Wat Phra Keo and That Luang. Despite the major role that Buddhism, its temples, and its priests have played in Laotian life, the average lowland Lao regulates a large part of daily activities in accordance with animistic concepts. Certain spirits (phi) are believed to have great power over human destiny and to be present throughout the material world, as well as within nonmaterial realms. Thus, each of the four universal elements (earth, sky, fire and water) has its special phi; every road, stream, village, house and person has a particular phi; forests and jungles are inhabited by phi. Evil phi can cause disease and must be propitiated by sacrifices.
The Lao-Theung and the Lao-Soung, including the upland tribes, are almost exclusively animists, although influenced by Buddhism to some extent. About 2% of the population are Christians, with about 60,000 Protestants and 40,000 Roman Catholics. Most Protestants are members of the Lao Evangelical Church or Seventh-Day Adventists, which are the only two officially recognized Protestant groups. Other minority religions include the Bahaism, Islam, Mahayana Buddhism, Taoism and Confucianism.
Though religious activity was discouraged by the state from 1976 to 1979, freedom of religion has been legally guaranteed since the constitution of 1991. However, the government reserves the right to serve as the final arbiter of permissible religious activities, which the government loosely defines as those practices which serve to promote national interests. Religious affairs are overseen by the Lao Front for National Construction (LFNC), an organisation of the Lao People's Revolutionary Party.