1198–1216

The Pontificate of Innocent III: the Peak of Papal Power

Innocent III was elected at 37. He taught that secular power derives its authority from the papal, "as the moon its light from the sun". He called himself the "Vicar of Christ", set "over nations and kingdoms".

He raised, then deposed, Emperor Otto IV, installing Frederick II in his place. He laid an interdict on France, forcing Philip Augustus to take back his lawful wife.

Innocent rejected both candidates for the see of Canterbury and appointed his own nominee, Stephen Langton. For this he excommunicated King John and placed England under interdict. After five years of struggle John capitulated in 1213, acknowledging England as a papal fief.

Under Innocent the Fourth Crusade began and the crusade against the Albigensians was proclaimed. The mendicant order of Francis was approved, and the practice of indulgences for crusade donors expanded. In 1215 the Fourth Lateran Council was convened.