Number of authors have sought to establish popular music as an important element within the Irish critical imagination. The popular music produced in Northern Ireland since the 1960s offers a key means of understanding the wider cultural and political fate of its people. In the 1960s the showbands ruled supreme throughout the length and breadth of Ireland. The emergence of the punk subculture in Northern Ireland is usually traced to the visit of The Clash to Belfast in 1977. The Clipper Carlton's played jazz instrumentals, novelty pop, calypso, rock 'n' roll, show tunes, Irish ballads, Country 'n' Western, any form of music that would elicit a response from their audience. Van Morrison may not have been as commercially successful as some, but his influence upon Irish popular music has been pervasive, even if much of the time that influence has been filtered through a variety of other sources.