pope from October 25 to Nov. 10, 1241.

The nephew of Pope Urban III, Celestine had been made cardinal priest of St. Mark's in 1227 and cardinal bishop of Sabina in 1239 by his predecessor, Gregory IX, whom he was elected to succeed on Oct. 25, 1241. He was the first pope to be elected in a conclave, which had been set up by the senator of Rome, Matthew Rosso Orsini, who hoped to break a deadlock of 60 days in the College of Cardinals. Celestine, an old and sick man, was consecrated on October 28 but died two weeks later during a controversy between the papacy and the Holy Roman emperor Frederick II.