Cornwall is a culturally Celtic nation, though Celtic-derived musical traditions had been moribund for some time before being revived during a late-20th-century roots revival.
In medieval Cornwall there are records of performances of ‘Miracle Plays’ in the Cornish language, with considerable musical involvement. Also (as frequently mentioned in the Launceston borough accounts) minstrels were hired to play for saints day celebrations. The richest families (including Arundell, Bodrugan, Bottreaux, Grenville, and Edgcumbe) retained their own minstrels, and many others employed minstrels on a casual basis. There were vigorous traditions of Morris dancing, mumming, guising, and social dance.
Then followed a long period of contention which included the Cornish Rebellion of 1497, the 1549 Prayer Book Rebellion, the Persecution of Recusants, the Poor Laws, and the English Civil War and Commonwealth (1642–1660). The consequences of these events disadvantaged many gentry who had previously employed their own minstrels or patronised itinerant performers. Over the same period in art music the use of modes was largely supplanted by use of major and minor keys. Altogether it was an extended cultural revolution, and it is unlikely that there were not musical casualties.
However, a number of manuscripts of dance music from the period 1750 to 1850 have now been found which tell of renewed patronage, employment of dancing masters, and a repertoire that spanned class barriers. Seasonal and community festivals, mumming and guising all flourished.
In the 19th century, the nonconformist and temperance movements were strong: these frowned on dancing and music, encouraged the demise of many customs, but fostered the choral and brass band traditions. Some traditional tunes were used for hymns and carols. Church Feast Days and Sunday School treats were widespread—a whole village processing behind a band of musicians leading them to a picnic site, where "Tea Treat Buns" (made with smuggled saffron) were distributed. This left a legacy of marches and polkas. Records exist of dancing in farmhouse kitchens, and in fish cellars Cornish ceilidhs called troyls were common, they are analogous to the fest-noz of the Bretons. Some community events survived, such as at Padstow and at Helston, where to this day, on 8 May, the townspeople dance the Furry Dance through the streets, in and out of shops, even through private houses. Thousands converge on Helston to witness the spectacle. The "Sans Day Carol" or "St Day Carol" is one of the many Cornish Christmas carols written in the 19th century. This carol and its melody were first transcribed from the singing of a villager in St Day in the parish of Gwennap: the lyrics are similar to those of "The Holly and the Ivy".