As a black baby, Pennant was fostered by an elderly white family in Slade Green, Greater London where he was the only black person, and where he states he was "bullied from day one" year after year, and beaten persistently - "Not just from rivals or other kids, the whole town.
After seeing legendary boxer Muhammad Ali (then known by his birth name of Cassius Clay) beat Henry Cooper, he adopted the name Cass.
[3] Pennant was a member and leader of the Inter City Firm (ICF) associated with the English football club West Ham United in the 1970s.
[3] He also worked as a consultant and played a cameo role as a riot police officer in the 2005 drama film about football hooliganism, Green Street.
[8] He also wrote the foreword for Manchester United football hooligan Colin Blaney's book Undesirables and contributed a short piece about Manchester United's rivalry with West Ham[9][10] Cass - The Cass Pennant movie review at The Hollywood News