On 9 March 1161, Tancred joined his uncle Simon, Prince of Taranto, in invading the palace, detained the king and queen, William I and Margaret, and their two sons, and incited a massacre of Muslims. Originally, the older of these two sons, Roger IV, Duke of Apulia, was destined to be crowned in place of William, but soon the populace supported the accession of Simon himself. Before Simon could put himself forward as a candidate, however, the rebellion had broken down and the people were restless. The insurrectionists were forced to free the king and retreat to their castles. Pardon was given them on condition of exile and many, including Tancred, took the offer. Tancred was exiled to Constantinople and returned to Sicily in 1166 upon the accession of the new king, his cousin William II.