Born in Paris, William started out in youth football with local side CFF Paris. He made the move into the French league, signing for Le Mans Union Club 72’s B team in 2005. William left France in the summer of 2008, joining Swiss club Neuchâtel Xamax, a side United faced in the 1985 UEFA Cup 3rd round. Two years later in 2010, he moved on again to Panetolikos from the Greek Superleague.
William tasted British football in 2012 when he moved to Coventry City in England. Circumstances at the club at the time meant he was unable to fulfill his contract and he moved on to Bury for a short spell.
In January 2014, William returned to Panetolikos for 18 months before being snapped up by fellow Greek side Veria FC. In the summer of 2016, William was back in the UK for trial with United and he signed a one year deal with the club in August.