Overview
The Guelphs and Ghibellines were factions supporting respectively the Pope and the Holy Roman Emperor in the Italian city-states of Central Italy and Northern Italy during the Middle Ages.
During the 12th and 13th centuries, rivalry between these two parties dominated political life across medieval Italy. The struggle for power between the Papacy and the Holy Roman Empire arose with the Investiture Controversy, which began in 1075 and ended with the Concordat of Worms in 1122.
History
Origins
The conflict between Guelphs and Ghibellines arose from the political divisions caused by the Investiture Controversy, about whether secular rulers or the pope had the authority to appoint bishops and abbots. Upon the death of Emperor Henry V, of the Salian dynasty, the dukes elected an opponent of his dynasty, Lothair III, as the new emperor. This displeased the house of Hohenstaufen, who were allied with and related to the old dynasty.
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