Pope John XX

Both Pope John XXI and Pope John XX refer to the same man: Pedro Juliao. There was some confusion with the numbering of popes who used the name John, which worsened when early records and books named an antipope as an official pope. When Pedro became the pope in 1276, he chose to use the name Pope John XXI, even though he was technically the 10th Pope John.

Early Life

The future Pope John XXI was born in Lisbon, Portugal circa 1215, but historians think he was born as early as 1210 or as late as 1220. Known as Pedro Juliao, he studied religion at the Lisbon Cathedral before traveling to France. It was there that he began focusing on medicine at either Montpelier or the University of Paris. In addition to medicine, he took classes in metaphysics and theology, which encouraged his interest in the Church. Pedro would also become close to Peter of Spain who many credit with the study of pharmacology.

Church Roles

Pedro’s background in medicine served him well as he began working with patients. Most of his early work focused on ophthalmology. Pedro later held different roles in the Church that led to his eventual papacy. He served as a prior and worked with King Alfonso III of Portugal who trusted the man to speak for him in the Church. Hoping to become more involved, Pedro tried to become the bishop of Lisbon but instead took a job as a schoolmaster. Pope Gregory X named him a Cardinal Bishop in 1273, a role that elevated him within the Church and gained him attention from other bishops.


Just two years after becoming Cardinal Bishop, Pedro found himself the new pope. Pope Adrian V passed away less than two months after becoming the pope. Bishops quickly nominated Pedro and named him the pope on September 8 before holding his coronation roughly a week later. During the Second Council of Lyon in 1274, an issued decree claimed that those responsible for electing the pope should remain in solitude and have their supplies restricted if the process took too long. Pope John XXI almost instantly reversed that decision, but it was one of the few things he accomplished during his papacy. He spent quite a bit of time fighting with a cardinal who would become Pope Nicholas III after John’s death. Though he had plans for missions and crusades, he never completed those plans.


John lived in the official papal residency but had an apartment built that he used to be alone and study medicine. While working there on May 14, 1277, the building suddenly collapsed and left him stuck beneath the rubble. Internal injuries that he sustained during the incident combined with workers unable to reach him led to the pope’s death just six days later. John XXI served as pope for less than nine months.


*Born: circa 1215 in Lisbon, Portugal
*Birth Name: Pedro Juliao
*Died: May 20, 1277
*Cause of Death: Internal injuries that he sustained when his apartment collapsed
*Papacy Began: September 8, 1276
*Papacy Ended: May 20, 1277
*Successor: Pope Nicholas III

Interesting Facts About Pope John XXI

*Pope John XXI was the first pope born and raised in Portugal. As of 2020, he remains the only pope in history born in that country.
*A small group of people living during this era believed that the pope was secretly a necromancer. According to some of the works that they left behind, God caused the building to collapse as a way to stop the pope.
*The final resting place of Pope John XXI is the Viterbo Cathedral in the Italian city of the same name. Though Pope Alexander IV was also interred there, workers accidentally demolished his tomb during the 16th century. Only the tomb of Pope John XXI is still known and marked, making it a popular tourist attraction.
*John XXI is one of just a few popes who had a profession outside of the Church. He studied medicine and worked as a doctor before focusing on the Church and becoming the pope.
*Before becoming the pope, he spent a lot of time studying the human eye. Many believe that he was the first to discover that glaucoma had a hard eye connection.