(1 May 1045–20 Dec. 1046: d. late 1047)
An elderly man respected in reforming circles, possibly related to the wealthy banking family of the Pierleoni, John Gratian was archpriest of St John at the Latin Gate when his godson Benedict IX, recently restored to the papal throne, made out a deed of abdication in his favour on 1 May 1045. It is widely conjectured that John was among those who persuaded him to take this step. A huge sum of money apparently changed hands; according to most sources Benedict sold the papal office, according to others the Roman people had to be bribed. The whole transaction remains obscure, probably because it was deliberately kept dark at the time; but the most likely explanation is that John, eager to secure Benedict's resignation, paid over the money with trusting naivety as compensation, either for him or, more likely, to his relatives or for both, for his relinquishing the papacy and its emoluments. It seems, however, that he did not personally benefit from the deal.
Although designated by Benedict as his successor (in itself a gross irregularity), there is some evidence that the forms of an election were observed; it is said that the new pope was given the name Gregory by popular acclaim. His accession was at first greeted with enthusiasm by friends of reform, and Peter Damian, reformer and doctor of the church (1007–72), congratulated him fulsomely, claiming that his election had struck a blow at simony (news of the financial deal had not yet leaked out). A cleric who served him in the curia, and became a close friend, was Hildebrand (later Gregory VII). But Gregory's position was far from assured. When King Henry III of Germany (1039–56) crossed the Alps in autumn 1046, his main object may have been to receive the imperial crown, but church reform and the restoration of order to the papacy, of the parlous condition of which he had been informed, were also in his mind. A synod over which he presided at Pavia prepared for what was to come by publishing a general prohibition of simony. Evidently ill at ease, Gregory went to meet him at Piacenza; he is said to have been courteously received, but nothing in fact is known of the meeting. On 20 Dec. he appeared before the synod of Sutri, near Rome, to which he had been cited along with Benedict IX and Silvester III. After the circumstances of his election had been investigated, the emperor and the synod pronounced him guilty of simony in obtaining the papal office, and deposed him. According to some accounts, he was brought to acknowledge his culpability and voluntarily laid down his office, judging himself unfit to hold it. But these, like the reports that it was Gregory and not Henry who summoned and presided over the synod, reflect later embarrassment that the emperor should have presumed to preside over a council and judge the supreme pontiff.
The synod had not determined what was to be done with Gregory. For the moment he was kept in custody, but eventually Henry decided, in view of the danger of allowing a deposed pope to remain in Rome, to take him back with him to exile in Germany. In the spring he set out, accompanied by Hildebrand, for ‘the banks of the Rhine’, where Bishop Hermann of Cologne, imperial chancellor for Italy, was commissioned to watch over him. When the emperor, on the sudden death of Clement II (9 Oct. 1047), questioned the episcopate about a successor, Bishop Wazo of Liège (1042–8) argued that Gregory should be restored since his deposition had been invalid, the pope being incapable of being judged by anyone. Henry was not persuaded, and in any case Gregory died at Cologne, of an illness which has not been identified, towards the end of the year.