The names of Italian political factions deriving from the German Welf, the family name of the Dukes of Bavaria, and Waiblingen, the name of the castle of the Hohenstaufen Dukes of Swabia. The terms were first used in 1235 during the conflict between Pope Gregory IX and Emperor Frederick II Hohenstaufen. The Guelfs were supporters of the papacy and belonged to the merchant class, while the Ghibellines, feudal land owners, sided with the emperor. The rivalry of these two factions is of particular significance to the history of Florence where the Guelfs succeeded in removing the Ghibellines from power in the 1260s. The Guelfs destroyed the palace of the Ghibelline Uberti family and built on its site the Palazzo Vecchio (1299-1310) as their seat of government.
Historical dictionary of Renaissance art. Lilian H. Zirpolo. 2008.