The festival, originally held over two days in September (but also held in September in 1933 and 1947, since C. S. Lewis's brother Warren is known to have attended), is one of the world's oldest classical choral music festivals. Publicity for it in 1719 addressed "Members of the yearly Musical Assembly in these parts". Its music obviously tended towards the ecclesiastical. In early gatherings, Purcell's setting of the Te Deum and Jubilate was a regular part of the repertoire until 1784, and Handel dominated 18th-century programmes with oratorios such as Alexander's Feast, Samson, Judas Maccabaeus and Messiah. Sir Samuel Hellier, guardian of the Hellier Stradivarius, was a "prominent figure". Haydn's The Creation was heard first in the festival of 1800. From 1840, Mendelssohn's Elijah was performed every year until 1930.
The 19th century saw the introduction of Rossini, Mozart and Beethoven, and the festival's fortunes were enhanced by the arrival of the railways. However, these also brought crowds, a phenomenon not always pleasing to the church authorities, although full seats uplifted the finances. In the 1870s, the festival was reduced to the three cathedral choirs, ending for a while the era of the visiting celebrity singer as a faction in the church sought to stress the "appropriate" nature of activities allowed in cathedrals. However, the civil authorities took issue with the ecclesiastical and the festival revived. Interestingly, works by J. S. Bach were not heard until the 1870s, soon to be followed by local composer Elgar, who began to be featured around the turn of the century and whose works dominated the festival for much of the 20th century as its emphasis shifted toward British musicians. Herbert Sumsion, organist at Gloucester between 1928 and 1967, particularly helped to promote the works of native composers, including premiering works of Howells, Finzi, and others. Parry's compositions were also performed regularly. His De Profundis was one of the earliest works to be commissioned especially for the festival and performed in 1891.
Delius in 1901 was another composer who introduced or conducted new works, with his Dance Rhapsody No. 1. Another was Ralph Vaughan Williams, whose Fantasia on a Theme by Thomas Tallis was premiered there in 1910, followed by the Five Mystical Songs in 1911 and the Fantasia on Christmas Carols in 1912, after which he co-featured with Elgar as a central prop to the musical repertoire. Sumsion fostered a relationship with Hungarian composer Zoltán Kodály and programmed Kodály's works at six Gloucester festivals. Other names include Gustav Holst, Arthur Sullivan, Herbert Howells, Gerald Finzi, William Walton, Arthur Bliss and Benjamin Britten and recently, Lennox Berkeley, John McCabe, William Mathias, Paul Patterson and James MacMillan.
A timeline of some of the more significant events in the festival's history from 1709 until the present day has been compiled by Anthony Boden: Three Choirs Festival timeline
In 1995, a Festival Society was established to provide a means for enthusiasts to actively participate in support for the Three Choirs Festival. The festival is funded by ticket sales, donations and sponsorships.
In 2010, the Three Choirs Festival Youth Choir was formed. Made up of singers aged 16–25, it has performed at every festival since then, under a variety of conductors. In 2012 in Hereford the Three Choirs Festival Youth Choir premiered Centuries of Meditation, a setting by Dobrinka Tabakova of words by Thomas Traherne.
The Philharmonia Orchestra began a rolling three-year formal residency at the festival in 2012.