1920 in the religious sense, from fundamental + -ist. Coined in American English to name a movement among Protestants c. 1920-25 based on scriptural inerrancy, etc., and associated with William Jennings Bryan, among others. The original notion might have been of "fundamental truths."
Fundamentalism is a protest against that rationalistic interpretation of Christianity which seeks to discredit supernaturalism. This rationalism, when full grown, scorns the miracles of the Old Testament, sets aside the virgin birth of our Lord as a thing unbelievable, laughs at the credulity of those who accept many of the New Testament miracles, reduces the resurrection of our Lord to the fact that death did not end his existence, and sweeps away the promises of his second coming as an idle dream. It matters not by what name these modernists are known. The simple fact is that, in robbing Christianity of its supernatural content, they are undermining the very foundations of our holy religion. They boast that they are strengthening the foundations and making Christianity more rational and more acceptable to thoughtful people. Christianity is rooted and grounded in supernaturalism, and when robbed of supernaturalism it ceases to be a religion and becomes an exalted system of ethics. [Curtis Lee Laws, Herald & Presbyter, July 19, 1922]
Fundamentalist is said (by George McCready Price) to have been first used in print by Curtis Lee Laws (1868-1946), editor of "The Watchman Examiner," a Baptist newspaper. The movement may have roots in the Presbyterian General Assembly of 1910, which drew up a list of five defining qualities of "true believers" which other evangelicals published in a mass-circulation series of books called "The Fundamentals." A World's Christian Fundamentals Association was founded in 1918. The words reached widespread use in the wake of the contentious Northern Baptist Convention of 1922 in Indianapolis. In denominational use, fundamentalist was opposed to modernist. Applied to other religions since 1956 (earliest extension is to the Muslim Brotherhood).
A new word has been coined into our vocabulary — two new words — 'Fundamentalist' and 'Fundamentalism.' They are not in the dictionaries as yet — unless in the very latest editions. But they are on everyone's tongue. [Address Delivered at the Opening of the Seminary, Sept. 20, 1922, by Professor Harry Lathrop Reed, printed in Auburn Seminary Record]
As "science teaching based on a fundamentalist interpretation of the Book of Genesis, the scientific theory attributing the origin of matter and life to immediate acts of God," opposed to evolutionism, it is attested from 1880. Century Dictionary (1897) defines creationism in this sense as "The doctrine that matter and all things were created, substantially as they now exist, by the fiat of an omnipotent Creator, and not gradually evolved or developed."
Creation science is attested by 1970 as an alternative name for a theory of science not inconsistent with Christian fundamentalism. Creationist (n.) in an "anti-Darwin" sense is attested by 1859 in a letter of Darwin's, and it is said to be used in Darwin's unpublished writings as far back as 1842.
James Ussher (1581-1656), Archbishop of Armagh, Primate of All Ireland, and Vice-Chancellor of Trinity College in Dublin was highly regarded in his day as a churchman and as a scholar. Of his many works, his treatise on chronology has proved the most durable. Based on an intricate correlation of Middle Eastern and Mediterranean histories and Holy writ, it was incorporated into an authorized version of the Bible printed in 1701, and thus came to be regarded with almost as much unquestioning reverence as the Bible itself. Having established the first day of creation as Sunday 23 October 4004 B.C. ... Ussher calculated the dates of other biblical events, concluding, for example, that Adam and Eve were driven from Paradise on Monday 10 November 4004 BC, and that the ark touched down on Mt Ararat on 5 May 1491 BC "on a Wednesday". [Craig, G.Y., and E.J. Jones, "A Geological Miscellany," Princeton University Press, 1982.]