John XXI
Pedro Juliao (Peter of Spain) · 1276 – 1277
The only Portuguese pope, a physician and philosopher who died when the ceiling of his study collapsed on him.
Pedro Juliao was a physician, philosopher, and the author of Summulae Logicales, the most widely used logic textbook of the medieval period. Born in Lisbon, he studied at the University of Paris, served as personal physician to several popes, and became pope himself in 1276. He showed interest in reconciling with the Eastern churches and ordered an investigation into the teachings condemned by the Bishop of Paris in 1277. His pontificate lasted only eight months. He was working in a newly built addition to the papal palace at Viterbo when the roof collapsed. He died of his injuries six days later.
A Scholar on Peter's Chair
John XXI was the rare pope who was also a genuine intellectual in his own right. His logic textbook was used in European universities for three centuries. Dante placed him in the Paradiso among the great lights of wisdom. His death by collapsing ceiling was bizarre and sudden, cutting short a pontificate that might have accomplished much.