Pope Boniface VIII issues the Papal bull Unam sanctam, claiming spiritual supremacy for the papacy.
Unam sanctam is a papal bull that was issued by Pope Boniface VIII on 18 November 1302. It laid 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 to belong to the Church and thus to attain salvation. The Pope further emphasized the higher position of the spiritual in comparison with the secular order. The historian Brian Tierney calls it "probably the most famous" document on church and state in medieval Europe. 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 was the definitive statement of the late medieval theory of hierocracy, which argued for the temporal as well as spiritual supremacy of the pope.
Pope Boniface VIII (Latin: Bonifatius PP. VIII; born Benedetto Caetani, c. 1230 – 11 October 1303) was the head of the Catholic Church and ruler of the Papal States from 24 December 1294 to his death in 1303. The Caetani family was of baronial origin, with connections to the papacy. He succeeded Pope Celestine V, who had abdicated from the papal throne. Boniface spent his early career abroad in diplomatic roles.
Boniface VIII put forward some of the strongest claims of any pope to temporal as well as spiritual power. He involved himself often with foreign affairs, including in France, Sicily, Italy and the First War of Scottish Independence. These views, and his chronic intervention in "temporal" affairs, led to many bitter quarrels with Albert I of Germany, Philip IV of France, and Dante Alighieri, who placed the pope in the Eighth Circle of Hell in his Divine Comedy, among the simoniacs.
Boniface systematized canon law by collecting it in a new volume, the Liber Sextus (1298), which continues to be important source material for canon lawyers. He established the first Catholic "jubilee" year to take place in Rome. Boniface had first entered into conflict with Philip IV of France in 1296 when the latter sought to reinforce the nascent nation state by imposing taxes on the clergy and barring them from administration of the law. Boniface excommunicated Philip and all others who prevented French clergy from traveling to the Holy See, after which the king sent his troops to attack the pope's residence in Anagni on 7 September 1303 and capture him. Boniface was held for three days and beaten badly.
King Philip IV pressured Pope Clement V of the Avignon Papacy into staging a posthumous trial of Boniface. He was accused of heresy and sodomy, but no verdict against him was delivered.