Answer
The Kingdom of West Francia intervened in power struggles during Pope Formosus's reign. The Pope had been excommunicated and deposed, but he returned to Rome and reclaimed his office. The King of West Francia, Charles the Bald, supported the antipope John XIII, and the Kingdom of Italy supported Formosus. In 897, Charles the Bald and the antipope marched on Rome and Formosus was forced to abdicate.