Unam Sanctam

On 18 November 1302, Pope Boniface VIII issued the Papal bull Unam sanctam which some historians consider one of the most extreme statements of Papal spiritual supremacy ever made. The original document is lost but a version of the text can be found in the registers of Boniface VIII in the Vatican Archives. The Bull lays down dogmatic propositions on the unity of the Catholic Church, the necessity of belonging to it for eternal salvation, the position of the pope as supreme head of the Church, and the duty thence arising of submission to the pope in order to belong to the Church and thus to attain salvation. The pope further emphasizes the higher position of the spiritual in comparison with the secular order.

The bull was promulgated during an ongoing dispute between Boniface VIII and Philip the Fair, King of France.

As long as England and France were at war with each other, neither was likely to participate in any expedition to the Holy Land. Benedict sent cardinal nuncios to each court to broker a truce. When this failed he then tried to get the parties to come to terms by cutting off some of the revenues financing the conflict. On 5 February 1296, Boniface issued the papal bull Clericis laicos forbidding clerics, without authority from the Holy See, to pay to laymen any part of their income or of the revenue of the Church; and likewise all emperors, kings, dukes, counts, etc. to receive such payments, under pain of excommunication.

Edward I of England responded with outlawry, a concept known from Roman law. This effectively withdrew the protection of the English Common Law from the clergy, and confiscated the temporal properties of bishops who refused his levies. As Edward was demanding an amount well above the tenth offered by the clergy, Archbishopric of Canterbury Robert Winchelsey left it to every individual clergyman to pay as he saw fit.

In August 1296 Philip of France countered with an embargo. A common wartime precaution, disallowing the export of horses, arms, and money, the embargo served primarily to keep the French clergy from sending taxes to the pope. By prohibiting the export of gold, silver, precious stones, or food from France to the Papal States, this had the effect of blocking a main source of papal revenue. Philip also banished from France papal agents raising funds for a new crusade in the Middle East.

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