Following the unexpected announcement that Pope Benedict XVI will resign as Supreme Pontiff on Feb. 28, the world's attention turned to Pope Gregory XII, the last pope to abdicate his place as head of the Roman Catholic Church.
Gregory XII, (whose birth name was Angelo Correr) served as the bishop of Rome from 1406 to 1415. He resigned to resolve a dispute over who should lead the Catholic Church in The Western Schism times (A.K.A. the split of the catholic church) and died two years after leaving his post.