 While Constantine, like the Massa, had been a vassal of the Republic of Pisa, Peter transferred his allegiance to the Republic of Genoa.In 1187, open conflict raged over the whole island of Sardinia between the Genoese and their factions and the Pisans and theirs.The Pisans mercilessly assaulted Genoese merchants in Cagliari and despoiled their landed possessions, evicting them from the "giudicato".