Concordat of Worms
He threw out the papal troops from Ancona and Spoleto, reclaiming the territory as imperial fiefs. He then demanded that Frederick of Sicily do homage for the duchies of Calabria and Apulia, and when Frederick refused to appear, Otto declared those fiefs forfeited. Otto then marched on Rome, and commanded Innocent to annul the Concordat of Worms, and to recognise the imperial crown's right to make nominations to all vacant benefices.