Cardinal in 1244.
Papaldiplomat.
Close confidant of popes for 30 years.
The Holy See was vacant for six months before his election.
Worked to free the Papal States and the papacy from the influence of foreign rulers.
Temporarily reunified the Franciscans who had split during an internal dispute over the definition of perfect poverty. Made the Vatican the permanent papal residence.
At the request of the Tatar khan he sent Franciscanmissionaries to Persia and China.