Pope John XXI (1215 – May 20, 1277), born Pedro Julião (Latin, Petrus Iulianus), a Portuguese also called Pedro Hispano (Latin, Petrus Hispanus, was Pope from 1276 until his death about eight months later. He was the only Portuguese Pope, although Damasus I can also be considered Portuguese, as he was born in territory that is nowadays in Portugal, and Paul IV also had a Portuguese maternal grandmother.
Pedro Julião, born between 1210 and 1220, was probably born in Lisbon. He started his studies at the episcopal school of Lisbon Cathedral, and later joined the University of Paris, although some historians claim that he was educated at Montpellier. Wherever he studied, he concentrated on medicine, theology, and Aristotle's dialectic, logic, physics and metaphysics.
From 1245 to 1250 he became known as Pedro Hispano (because he came from Hispania, the Iberian Peninsula) and taught medicine at the university of Siena, where he wrote the Summulae Logicales, a reference manual on Aristotelian logic that remained in use in European universities for more than 300 years (see Peter of Spain for some controversies). He became famous as a university teacher, then returned to Lisbon. In the courts of Guimarães he was the councilor and spokesman of the king Afonso III of Portugal (1248–79) in church matters; later, becoming prior of Guimarães. He tried to become Bishop of Lisbon, but he was defeated. Instead, he became the master of the school of Lisbon. A notable philosopher, he was also the responsible for the creation of the Square of opposition.
Pedro became the physician of Pope Gregory X (1271–76).
Though much of John XXI's brief papacy was dominated by the powerful Cardinal Giovanni Gaetano Orsini (who succeeded him as Pope Nicholas III), John attempted to launch a crusade for the Holy Land, pushed for a union with the Eastern church, and did what he could to maintain peace between the Christian nations. He also launched a drive to convert the Tatars, which came to nothing.
The Pope had a new wing added to his palace at Viterbo; it was poorly built, and while he lay sleeping part of the roof fell in and he was seriously injured. John XXI died eight days later, probably as the only pope to end his life by an actual accident, on May 20, 1277. He was buried in the Duomo di Viterbo where his tomb can still be seen.
After his death, it was rumored that John XXI had actually been a magician (a suspicion frequently directed towards the preciously few scholars among medieval popes even during their papacy; see e.g., Sylvester II), and that he was writing a heretical treatise in the room that collapsed on him, by an Act of God, it was infered.
In The Divine Comedy Dante sees John XXI (referred to as "Pietro Spano") in the Heaven of the Sun with the other spirits of great religious scholars.
Surprisingly, one of the most comprehensive recipe books for pre- and post-coital contraception was written by Pedro Hispano, who offered advice on birth control and how to provoke menstruation in his immensely popular Thesaurus Pauperum (Treasure of the Poor). Many of Peter’s recipes have been found surprisingly effective by contemporary research, and it is believed that women in antiquity had more control over their reproduction than previously believed (Riddle, 1994).