Blackwell was founder of Island Records, one of the biggest independent record companies. It was only in the 1990s that he sold the company to Polygram. In 1997 he left his post as CEO to start up with a new label, Palm Pictures.

Blackwell's family lived in Jamaica where he had his first contacts to Jamaican music. He produced his first records and later, when he went to the UK, he released Jamaican 45's on his Black Swan R'n'B and Island labels. Blackwell became famous for "discovering" Bob Marley. In 1976 Blackwell financed the recording sessions for Rico's landmark album Man From Wareika. It's a pitty that Rico was not well supported by the company after the release.