The Plastic Ono Band began as John Lennon's first solo band. It was formed during a plane trip to Canada where they went to headline the Toronto Peace Festival in September 1969.
The original members from 1969 were:
John Lennon (from The Beatles) - vocals / rhythm guitar
Eric Clapton (formerly of Cream and The Yardbirds)- backup vocals / lead guitar
Klaus Voorman - bass guitar
Alan White (from Yes) - drums
Yoko Ono - vocals
They performed at the festival along with other artists such as Chuck Berry, Little Richard, Jerry Lee Lewis, Bo Diddley, Alice Cooper, Chicago, and The Doors.
Lennon and the band were escorted into Toronto's Varsity Stadium by a long procession of motorcycle riders from the Hell's Angels motorcycle gang as protection.
The Plastic Ono Band went on to perform several other concerts sporadically between 1969 and 1975, with different lineups and slightly changed band name. (For example, a 1975 show was billed as The Plastic U.F.Ono Band.) They also recorded several albums with various lineups for John Lennon and Yoko Ono in the early 1970s.
The Plastic Ono Band reformed in 2009 with original member Yoko Ono, and Sean Lennon (the son of the late John Lennon), on guitar. This resulted in a critically acclaimed new album, plus a short U.S. tour.
