movement in American Protestantism that arose in the late 19th century in reaction to theological modernism, which aimed to revise traditional Christian beliefs to accommodate new developments in the natural and social sciences, especially the advent of the theory of biological evolution. In keeping with traditional Christian doctrines concerning biblical interpretation, the mission of Jesus Christ, and the role of the church in society, fundamentalists affirmed a core of Christian beliefs that included the historical accuracy of the Bible, the imminent and physical Second Coming of Jesus Christ, and Christ’s Virgin Birth, Resurrection (see resurrection), and Atonement (see atonement). Fundamentalism became a significant phenomenon in the early 20th century and remained an influential movement in American society into the 21st century. See also Evangelical church.
Fundamentalist worship practices, which are heavily influenced by revivalism, usually feature a sermon with congregational singing and prayer, though there can be considerable variation from denomination to denomination. Although fundamentalists are not notably ascetic, they do observe certain prohibitions. Most fundamentalists do not smoke, drink alcoholic beverages, dance, or attend movies or plays. At most fundamentalist schools and institutes, these practices are strictly forbidden.
Origins
During the 19th century, major challenges to traditional Christian teachings arose on several fronts. Geologic discoveries revealed that the Earth was far older than the few thousand years suggested by a literal reading of the biblical book of Genesis. The work of Charles Darwin (1809–82) and his colleagues established that human beings as a species had emerged over millions of years through a process of evolution, rather than suddenly by divine fiat. Social scientists and philosophers influenced by Herbert Spencer (1820–1903) advocated a parallel theory of progressive social evolution that refuted the traditional religious understanding of human sin, which was predicated on the notion that, after the fall from grace, the human condition was corrupt beyond repair. Meanwhile, some ministers in various denominations ceased to emphasize the conversion of individuals to the religious life and instead propounded a “social gospel” that viewed progressive social change as a means of building the kingdom of God on Earth.
A more direct challenge to traditional Christianity came from scholars who adopted a critical and historical approach to studying and interpreting the Bible. This perspective, known as modernism, treated the books of the Bible—especially the first five (the Pentateuch)—not as simple documents written by a single author but as complex texts constructed by multiple authors from several older sources. Although modernism offered a solution to many problems posed by seemingly contradictory biblical passages, it also raised severe doubts about the historical accuracy of the biblical text, leading scholars to revise the traditional history of the biblical era and to reconsider the nature of biblical authority. (For a discussion of modernism in the history of Roman Catholicism, see Modernism.)
The issue of biblical authority was crucial to American Protestantism, which had inherited the fundamental doctrine of sola Scriptura (Latin: “Scripture alone”

as enunciated by Martin Luther (1483–1546) and other 16th-century Reformers. Thus, any challenge to scriptural integrity had the potential to undermine Christianity as they understood and practiced it. In response to this challenge, theologians at the Princeton Theological Seminary argued for the verbal (word-for-word) inspiration of Scripture and affirmed that the Bible was not only infallible (correct when it spoke on matters of faith and morals) but inerrant (correct when it spoke on any matters, including history and science).
As the theologians at Princeton developed their new approach, John Nelson Darby, one of the earliest leaders of the Plymouth Brethren (a British free church movement emphasizing biblical prophecy and the Second Coming of Christ), introduced a very different theological perspective, called dispensationalism. First taught to the Brethren in the mid-19th century, dispensationalism maintained that history is divided into distinct periods, or “dispensations,” during which God acts in different ways toward his chosen people. The present period, according to dispensationalism, was one of expectant waiting for the imminent return of Jesus Christ. Dispensationalists believed in an apocalyptic millennialism that foretold the Rapture (the bodily rescue of the chosen by God) and the subsequent cataclysmic events of the Last Days, such as the persecutions by the Antichrist and the Battle of Armageddon (see also eschatology).
Christian fundamentalism (American Protestant movement) -- Britannica Online Encyclopedia