Why did William of Ockham write political works against the papacy?

William of Ockham wrote political works against the papacy primarily due to his involvement in a dispute over Franciscan poverty and his subsequent conflict with Pope John XXII.1

Ockham, a Franciscan friar, believed that Christ and his Apostles had renounced all ownership of property. He argued that the Franciscan order was justified in following this example of absolute poverty. When he was instructed to study papal bulls regarding this issue, he concluded that John XXII’s teachings contained errors, leading him to view the pope as a heretic who had forfeited his mandate.1

Following his flight from Avignon in 1328, Ockham sought protection under Emperor Louis IV. From that point on, he wrote fervently to defend both the strict Franciscan ideal of poverty and the authority of the empire against the papacy. He maintained that the pope's power is limited by the freedom of Christians and natural law, asserting that the church is a community of the faithful without an infallible authority.1