Elected emperor in 1211, Frederick found his imperial inheritance threatened by growing noble power. Secure only in his maternal inheritance in Sicily, in 1216 he recognized it as a papal fief. This provided a strong base throughout his reign, offering both material assistance and intellectual inspiration in his imperial schemes. Strong in Sicily but with ambitions in Germany, Frederick required full control of Italy before progressing north of the Alps. This threatened papal independence and the freedoms of the Lombard cities granted in 1183.
Schemes to separate papal and Lombardic interests failed. Frederick intended the 1226 diet at Cremona to be the occasion for re-establishing imperial authority in Lombardy, but provoked instead a hostile revival of the Lombard League. Papal support courted through promises of a crusade
Was lost since failure at Cremona made Frederick unwilling to depart, but excommunication for breach of his vow forced his hand. Success on crusade failed to win desired Church support at home, and he returned in 1229 to repulse a papal attack on Naples. Reconciliation with Rome in 1230 was followed by moves to centralize the government of his territories, which served only to renew hostility.
At Mainz in 1235 Frederick annulled the 1183 treaty, effectively declaring war on Lombardy and, after a failed attempt at mediation, the pope joined Frederick's enemies. Victorious over the
Milanese at Cortenuova in 1237, Frederick failed to capture Brescia in 1239 and his initiative faltered. Excommunicated in 1239, in 1240 the war against him gained crusading status, but only in 1245 did the papacy declare him deposed as emperor. Frederick fought on, despite defeat in 1248 at Parma, until his death at Florentino in 1250. Frederick left a crippling legacy of war to his family and the continued enmity of the papacy was to lead to the eventual destruction of the Hohenstaufens in 1268.
R. Oram
World History
