Pope John XXI

John XXI. (actually Peter Juliani or Peter or Pedro Hispanus Julião or Peter Rebuli - Giuliani; * 1205 in Lisbon, † May 20 1277 in Viterbo) was Pope from September 8 1276 until his death on May 20, 1277th

The counting of John XXI. as twenty-first pope of this name goes back to a medieval error, see John XX.


He was the son of a wealthy Portuguese physician and pharmacist named Julianus, therefore, the form of the name Peter Juliani ( Pedro Julião ).

He received at schools in Lisbon and León His first training. Then he moved to the University of Paris ( Sorbonne ), where he studied under Albertus Magnus. In 1245 he earned a master's degree in philosophy and in medicine. Then he went to southern Italy, where he deepened his knowledge of medicine in Salerno and Palermo and due to good contacts with the court of Frederick II as professor artis medicinae was appointed. Since 1247 he taught as Physicus at the newly founded General Studies from Siena. During this time, probably originated most of his medical writings.

His economic situation in Siena said to have been unfavorable. His apartment was on the slum where he got the inspiration for his then -known work pauperum thesaurus ( treasure of the poor ). It was a comprehensive collection of recipes, adapted to the possibilities of Unbegüteten. He wrote about ophthalmology and surgery, on the doctrine of the soul and the function of the heart, on abortion and contraception, etc.

Often writings on philosophy and logic are attributed to them, especially the Summulae logicales, the most popular medieval Introduction to Logic. This write-up is problematic, because the identification of John XXI. is not saved with the logician Peter Hispanus and controversial.

The future career

Around 1260 appointed Ottobuono Fieschi, Conte di Lavagna, who later became Pope Adrian V., the professor of medicine to his personal physician. From that Pope Gregory X recruited him as a archiater (Hof and personal physician ).

Peter climbed the ecclesiastical ladder, was built in 1273 Archbishop of Braga and Cardinal Bishop of Tusculum. He was 1274 participants at the second Council of Lyons. On September 8, 1276 the now about 60 years in the conclave in Viterbo to heated discussions elected Pope. In the conclave, the influence of Cardinal Giovanni Gaetano Orsini was the decisive factor in favor of his choice.

His projects as Pope

He resided exclusively in Viterbo. His pontificate lasted less than nine months, but he started large projects. He tried to bring peace between Philip III. , France and Alfonso X of Castile. He tried to preserve the Union with the Orthodox Church from 1274. He also tried unsuccessfully to initiate a crusade. He also gave suggestions for curriculum reform in the universities and sponsored scholarships for gifted students and took his own studies on again. To this end, he let grow on the back of the papal palace in Viterbo, a private library.

On a May evening in 1277 he was buried in it with falling masonry and died of his injuries a short time later.

This sudden death was the church at that time suspect. It took the view that something evil had happened. In a Chronicle reported a Dominican monk: This heretical black artists has been personally strangled in his palace by the devil!

The tomb of John XXI. located in the San Lorenzo Cathedral in Viterbo.


  • Tractatus duodecim Petri Hispani. Breda Deventer 1528 ( Digitized edition of the University and State Library Dusseldorf )