After seeing the Beatles and many other bands in Liverpool as a young boy at the age of 12, he decided to be a bass player. In 1966 Mark Clarke played with the Kegmen, in 1968 with the Locomotive and late 1968 with St. James Infirmary. Liverpool Echo called him in an article "The Joe Cocker of Liverpool". After a year of local gigs he moved to London, where he was introduced to Clem Clempson, who played at that time in Colosseum. After some time Mark was asked by Jon Hiseman to join Colosseum in the summer 1970 and he played in the band until the split late 1971, and again 21 years after the reunion in 1994 till the farewell in 2015. After Colosseum split he was briefly around the turn of the years 1971/1972 a member of Uriah Heep, performing on one studio track, "The Wizard", on the 1972 album Demons and Wizards. In the beginning of 1973 he became a member of Jon Hiseman's Tempest and played bass on the two Tempeststudio albums with Allan Holdsworth, Ollie Halsall and Paul Williams, and a live album issued later. He also played bass on Ken Hensley's solo albums. In 1975 he formed Natural Gas with Joey Molland, Jerry Shirley and Peter Wood. He also played shortly with Ritchie Blackmore's Rainbow. In 1980 he started working with Billy Squier and recorded Don't Say No, The Stroke, In the Dark and many other albums with him. In 1986 he toured with The Monkees, and until recently still worked with Davy Jones. Clarke has also worked twice in 1984-1985 and 1995-1996 with Mountain, Ian Hunter and Torque, recording albums with all of them. With Colosseum he played again from the reunion in 1994 to the farewell concert at the Shepherd's Bush Empire in London on 28 February 2015. In 2010 Mark Clarke released his first solo albumMoving to the Moon, which was co-produced by Ray DeTone, who also played all guitars on the record. In 2017 Mark Clarke became a member of a new trio band called JCM. Other members of the band were drummer Jon Hiseman and guitarist Clem Clempson. The band recorded an album "Heroes" late in 2017 and it was released in April 2018. JCM begun touring Europe on 7 April 2018 but the tour ended after the show on the 22nd of April in Bonn due Jon Hiseman*s illness. Rest dates of the tour were cancelled. Jon Hiseman died in June 2018 which initially appeared to be the end of JCM, however in early 2019 it was announced that band would continue with Ralph Salmins taking over drums. Tours of Europe and the UK took place throughout 2019.