Charles I of Naples and Sicily, whose…

Charles I of Naples and Sicily, whose expansionist policies have taken him on extensive campaigns in the Balkans against the resuscitated Greek empire, is the target of a conspiracy in which important foreign leaders, including Emperor Michael VIII Palaiologos and Peter III of Aragon, move to prevent Charles from invading the empire.

Many Ghibelline officials had fled the Kingdom of Sicily to the court of Peter III of Aragon, who had married Constance, the daughter and heir of Manfred.

Manfred's former chancellor, John of Procida, had arranged contact between Michael, Peter and the refugees at his court, and conspirators on the island of Sicily itself.

Peter had begun to assemble a fleet at Barcelona, ostensibly for another Crusade to Tunis.

In fact, the master-plan of John of Procida is to place Peter on the throne of Sicily, his Hohenstaufen inheritance.