Guelphs and Ghibellines, two rival groups in medieval Italian politics. (For origin of the names, When Frederick Barbarossa, the Holy Roman emperor, invaded northern Italy in 1154, his Italian supporters became known as Ghibellines. The pope and leaders of the Lombard League were the Guelphs.
After 1250, when Barbarossa's grandson Frederick II died, the Holy Roman emperors ceased being a serious threat to northern Italy. Guelph and Ghibelline then became names of feuding parties within northern Italian cities.