Italian cities kept fighting pope versus emperor for generations
Guelphs backed the pope and Ghibellines the Holy Roman Emperor across central and northern Italian city-states in the twelfth and thirteenth centuries. The feud grew from the Investiture Controversy over who appointed bishops, then outlived the original imperial–papal duel as local brand warfare.
The names began as German battle cries. Guelph is an Italian rendering of Welf, the family of the dukes of Bavaria that included Welf II and Henry the Lion. At the siege of Weinsberg in 1140, the Welfs reportedly shouted their name while Conrad III's Hohenstaufen troops yelled Wibellingen, after the town now called Waiblingen, which Italians turned into Ghibellino. So the Hohenstaufen camp became the Ghibellines, the imperial party, and the Welf camp the Guelphs, the papal party.
Behind the shouting lay the Investiture Controversy, the 1075 to 1122 fight over whether kings or the pope should appoint bishops and abbots, settled on paper at Worms. When the Salian emperor Henry V died, the dukes picked Lothair III, a foe of the old dynasty, which angered the related Hohenstaufens. Lothair sought papal protection and handed over imperial rights, sparking war in Germany. After he died the Hohenstaufen Conrad III was elected, but Lothair's Welf heir Henry the Proud kept fighting. Early in the thirteenth century the contest replayed between Philip of Swabia and the Welf Otto of Brunswick; Otto won the crown, broke with the pope, was excommunicated and gave way to Frederick II, who was hostile to both Otto and Rome. Gregory IX excommunicated Frederick in 1227 for not crusading, then again for crusading while banned.
In Italy the labels took on a life of their own. Towns fearing an expanding Papal States leaned Ghibelline, while those wanting distance from the emperor went Guelph, and a small city often picked the opposite side from its big neighbour. Guelph Florence met Ghibelline Siena at Montaperti in 1260, and Pisa stayed Ghibelline against Guelph Genoa and Florence. Within a single city, loyalties could split by guild or district and flip after an upheaval.
The feud dominated Italian politics through the twelfth and thirteenth centuries and outlived the pope-versus-emperor quarrel that spawned it. It faded in the fourteenth century, as states and lay society began pushing back against church interference altogether.
Source: Guelphs and Ghibellines
