Celestine V was born to a poor family, the eleventh of twelve children, and joined a monastery at a young age. His whole life was marked by extreme piousness: he founded the Celestine Order, and the papacy was forced on him. In fact, it's reported that he attempted to flee from the College of Cardinals, but they kept him in place. He took the seat in July 1254, and one of his first actions (with his new power of infallibility) was to set up a rule allowing popes to abdicate their power. He abdicated just a few months later in December, so he could pursue his ascetic life at the monastery.

This didn't really work out for him, at least in this life: his wicked, wicked successor Boniface VIII imprisoned him until his death two years later. Officially Celestine died from illness, although it was rumored at the time that Boniface did him in. He's now considered a saint.