Tetbury is a small town and civil parish within the Cotswold district of Gloucestershire, England. It lies on the site of an ancient hill fort, on which an Anglo-Saxon monastery was founded, probably by Ine of Wessex, in 681. The population of the parish was 5,250 in the 2001 census, increasing to 5,472 at the 2011 census. During the Middle Ages, Tetbury became an important market for Cotswold wool and yarn.