guelph

Etymology

The word came into English from Italian guelfo, which traces back to Middle High German Welf, the name of a Bavarian dynasty. Welf II, Duke of Bavaria, inherited possessions including Tuscany, Ferrara, Modena, Mantua and Reggio from his Italian wife, the Countess Matilda of Tuscany — lands that played a part in the Investiture Controversy. Because the Welf dynasty backed the Pope in that dispute, the Pope's supporters in Italy became known as Guelfi.