Page "Papal States" Paragraph 6

Other donations soon followed, mainly in mainland Italy but also in the provinces, but the Church held all of these lands as a private landowner, not as a sovereign entity.

When in the fifth century the Italian peninsula passed under the control of first Odoacer and then the Ostrogoths, the church organization in Italy, and the bishop of Rome as its head, submitted to their sovereign authority while asserting their spiritual primacy over the whole Church.