The political fog in Italy had not yet cleared when Clement V was elected to the papacy. The struggle between Guelphs and Ghibellines, in so far as it was still being waged, lacked political principles or established beliefs as to the inherent superiority of pope or emperor. It served, rather, to obscure the real issues of controversy, such as the determination of regional hegemonies and of political, legal, and proprietary relations among opposing political factions. Between the Battle of Benevento, when Charles I of Anjou defeated and killed Manfred Hohenstaufen (26 February 1266), and the Sicilian Vespers, when the French garrison in Palermo was massacred and the crown of Sicily offered to Pedro of Aragon as Manfred's heir (30 March 1282), the Guelphs had enjoyed virtually unchallenged hegemony under the lead of the papacy, the Angevin monarchy, and Florence. Important communes in the Guelph taglia included Perugia, Siena, Bologna, Cremona, and Padua. The Sicilian Vespers and the following peace treaty, however, substantially altered the political balance, undermining Angevin and papal power everywhere. Guelphism became a vague concept, easily manipulated to advance ever changing, particularist interests.

The Florentines provide a case in point. On a theoretical level, they identified themselves as ‘the faithful and devoted people of the Holy Church, lovers of the popolo and the commune, and supporters of the liberty of Florence and of the parte guelpha’.