In 1154, Roger II died and the kingdom of Sicily passed to his fourth son, William I. William dispossessed his half-brother Simon immediately, claiming that Taranto was too important a fief to go to an illegitimate son. Simon held a grudge against the king and was called upon by Matthew Bonnellus to lead the revolt in the capital city of Palermo in 1161.
In 1154, Roger II passed away, and his fourth son, William I, inherited the kingdom of Sicily. William immediately dispossessed his half-brother Simon, asserting that Taranto was too significant a fief to go to an illegitimate son. Simon harbored resentment against the king and was urged by Matthew Bonnellus to lead the rebellion in Palermo in 1161.