Gospel music is a genre of Christian music. The creation, performance, significance, and even the definition of gospel music varies according to culture and social context. Gospel music is composed and performed for many purposes, including aesthetic pleasure, religious or ceremonial purposes, and as an entertainment product for the marketplace. Gospel music usually has dominant vocals (often with strong use of harmony) with Christian lyrics. Gospel music can be traced to the early 17th century, with roots in the black oral tradition. Hymns and sacred songs were often repeated in a call and response fashion. Most of the churches relied on hand clapping and foot stomping as rhythmic accompaniment. Most of the singing was done a cappella. The first published use of the term "gospel song" probably appeared in 1874. The original gospel songs were written and composed by authors such as George F. Root, Philip Bliss, Charles H. Gabriel, William Howard Doane, and Fanny Crosby. Gospel music publishing houses emerged. The advent of radio in the 1920s greatly increased the audience for gospel music. Following World War II, gospel music moved into major auditoriums, and gospel music concerts became quite elaborate. Gospel blues is a blues-based form of gospel music (a combination of blues guitar and evangelistic lyrics).[not verified in body] Southern gospel used all male, tenor-lead-baritone-bass quartet make-up. Progressive Southern gospel is an American music genre that has grown out of Southern gospel over the past couple of decades. Christian country music, sometimes referred to as country gospel music, is a subgenre of gospel music with a country flair. It peaked in popularity in the mid-1990s. Bluegrass gospel music is rooted in American mountain music. Celtic gospel music infuses gospel music with a Celtic flair, and is quite popular in countries such as Ireland. British black gospel refers to Gospel music of the African diaspora, which has been produced in the UK. Some proponents of "standard" hymns generally dislike gospel music of the late 19th and early 20th centuries. Today, with historical distance, there is a greater acceptance of such gospel songs into official denominational hymnals.