Jethro Tull were a British rock group, formed in Luton, Bedfordshire, in December 1967. Initially playing blues rock, the band soon developed its sound to incorporate elements of British folk music and hard rock to forge a progressive rock signature. The band was led by vocalist/flautist/guitarist Ian Anderson, and have included other significant members such as guitarist Martin Barre, keyboardist John Evan, drummers Clive Bunker, Doane Perry, and Barriemore Barlow, and bassists Glenn Cornick, Jeffrey Hammond, and Dave Pegg.