PIETRO DI MORRONE did not want to be pope. When he was elected as Celestine V in 1294 he was in his 80s and had been living as a hermit in the mountains of Abruzzo in central Italy. His fans hoped he would be holier than his predecessors. Perhaps he was: five months later he resigned, after changing the rules to allow him to do so. Benedict XVI has twice visited Celestine's tomb. That voluntary abdication was a first. Three previous popes to leave the See of Peter were all forced out. Martin I was pope for four years until 653, when he was charged with treason. He was stripped naked in public, his tunic was ripped and his pastoral staff was broken over his head. From exile in the Crimea he wrote that he prayed for the safety of the faithful and "the pastor who is now placed over there"; this epistle was taken as proof of his resignation. Benedict V held the position for only a month until June 964 when Otto I (of the Holy Roman Empire) demanded his resignation in favour of his protégé, Leo VIII. Benedict IX stayed for a little longer. He was in his early 20s when he was elected in 1032, and was the only one to reign in three separate stints. Violent and debauched, his papacy was bought for him by his father. Over 16 years he employed a private army to keep himself in Rome and once sold his office for a dowry. He was forcibly removed, and succeeded by Damasus II. The happier precedent set by Celestine helped Gregory XII. He ended his nine-year papacy by resigning in 1415 as part of a deal that ended the Western schism in the church, which had followed a contested election in 1378. Benedict XVI's resignation seems relatively peaceful. He will not be humiliated in public, nor immortalised by a poet as he "who made from cowardice the great refusal" (a gibe that Dante in the 14th century seemingly threw at Celestine). He will still live in the Vatican, something which none of these five could do. But his departure echoes Celestine's resignation, which was "because of my lowliness, my desire for a more perfect life, my great age and infirmities."