The Rolling Stones are an English rock band formed in London, England in 1962. The original line-up consisted of Mick Jagger (lead vocals), Keith Richards (lead guitar, backing vocals), Brian Jones (rhythm guitar, harmonica), Ian Stewart (piano), Bill Wyman (bass) and Charlie Watts (drums). Stewart was removed from the official line-up in 1963 but continued as a touring member until his death in 1985. Jones left the band less than a month prior to his death in 1969, having already been replaced by Mick Taylor, who remained until 1974. After Taylor left the band, Ronnie Wood took his place in 1975 and has been on guitar in tandem with Richards ever since. Following Wyman's departure in 1993, Darryl Jones joined as their touring bassist. Other touring keyboardists for the band have been Nicky Hopkins (1967–82), Billy Preston (through the mid 1970s) and Chuck Leavell (1982-present). The band was first led by Jones, but after teaming as the band's songwriters, Jagger and Richards assumed leadership while Jones dealt with legal and personal troubles.The Rolling Stones were at the forefront of the British Invasion of bands that became popular in the US in 1964. The band identified with the youthful and rebellious counterculture of the 1960s. They were instrumental in making blues a major part of rock and roll. After a short period of musical experimentation that peaked with the psychedelic album Their Satanic Majesties Request (1967), the group returned to its "bluesy" roots with Beggars Banquet (1968) which along with its follow-ups: Let It Bleed (1969), Sticky Fingers (1971) and Exile on Main St. (1972), is generally considered to be the band's best work and is seen as their "Golden Age". During this period, they were first introduced on stage as "The World's Greatest Rock and Roll Band". Musicologist Robert Palmer attributed the "remarkable endurance" of the Rolling Stones to being "rooted in traditional verities, in rhythm-and-blues and soul music", while "more ephemeral pop fashions have come and gone".