The earliest recorded uses of choral singing are for Christian worship, in particular the unison singing of plainchant. Medieval monastic choirs often numbered over 50, while cathedrals, collegiate churches, and household chapels supported similar-sized choirs of men and boys. Convents, naturally, employed women's voices. Contrast was provided by alternating choral chant with passages sung by soloists. These sections were later set polyphonically and by the 15th cent. were assigned to a small choir, generally in four or five parts. By the mid-16th cent. London's Chapel Royal numbered around 32 men and 12 boys. The post-Reformation choir was usually split into two antiphonal groups: cantoris on the precentor's side and decani opposite on the dean's side.
During the Commonwealth (1649–60) choirs were disbanded, although at the Restoration Charles II conscripted the best choirboys throughout the country (including Purcell) for his new Chapel Royal. Short choruses were an important element in the masque and Restoration stage works, and it was on this tradition that Handel built his new genre, the English oratorio. Here the chorus (usually sung by around 24 singers including the soloists) often played an important dramatic role, as in the many double choruses of Israel in Egypt (1739). The 1784 Handel celebrations at Westminster abbey, with nearly 300 singers and almost as many instrumentalists, began a tradition of gargantuan performances that continued in the Handel festivals, using thousands of performers, inaugurated at London's Crystal Palace in 1857.
The 19th cent. saw the growth of countless amateur choral societies throughout Britain, now including female voices (except for male-voice choirs cultivated especially in Wales). Revivals of favourites by Handel (especially Messiah), Haydn, and, later, Bach were balanced by new commissions such as Mendelssohn's Elijah for the Birmingham Festival (1846). Evangelical movements formed choirs to sing hymns and gospel songs, and John Curwen's educational tonic sol-fa method opened up whole repertoires to singers unable to read conventional notation.
Some choirs, like the various Bach choirs around the country, concentrate on the music of a particular composer. During the last few decades, consorts of solo voices have specialized in early repertories such as madrigals, while small expert groups like the Monteverdi and Taverner choirs have adopted ‘authentic’ forces in an attempt to recreate earlier performing styles. See also Three Choirs Festival.
"choirs." The Oxford Companion to British History. . Encyclopedia.com. (August 14, 2018). http://www.encyclopedia.com/history/encyclopedias-almanacs-transcripts-and-maps/choirs
"choirs." The Oxford Companion to British History. . Retrieved August 14, 2018 from Encyclopedia.com: http://www.encyclopedia.com/history/encyclopedias-almanacs-transcripts-and-maps/choirs