The historian Johann Georg Estor made the claim that he was the son of a blacksmith. As a youth he was sent to study in Rome at the monastery of St. Mary on the Aventine, where, according to some unconfirmed sources, his uncle was abbot of a monastery on the Aventine Hill. Among his masters were the erudite Lawrence, archbishop of Amalfi, and Johannes Gratianus, the future Pope Gregory VI. When the latter was deposed by Holy Roman Emperor Henry III and exiled to Germany, Hildebrand followed him to Cologne. According to some chroniclers, Hildebrand moved to Cluny after Gregory VI's death, which occurred in 1048; though his declaration to have become a monk at Cluny must not be taken literally. He then accompanied Abbot Bruno of Toul to Rome; there, Bruno was elected pope, choosing the name Leo IX, and named Hildebrand as deacon and papal administrator. In 1054 Leo sent Hildebrand as his legate to Tours in France in the wake of the controversy created by Berengar of Tours. At Leo's death, the new pope, Victor II, confirmed him as legate, while Victor's successor Stephen IX sent him and Anselm of Lucca to Germany to obtain recognition from Empress Agnes. Stephen died before being able to return to Rome, but Hildebrand was successful; he was then instrumental in overcoming the crisis caused by the Roman aristocracy's election of an antipope, Benedict X, who, thanks also to Agnes's support, was replaced by the Bishop of Florence, Nicholas II. With the help of 300 Norman knights sent by Richard of Aversa, Hildebrand personally led the conquest of the castle of Galeria Antica where Benedict had taken refuge. Between 1058 and 1059, he was made archdeacon of the Roman church, becoming the most important figure in the papal administration. He was again the most powerful figure behind the election of Anselm of Lucca the Elder as Pope Alexander II in the papal election of October 1061. The new pope put forward the reform program devised by Hildebrand and his followers. In his years as papal advisor, Hildebrand had an important role in the reconciliation with the Norman kingdom of southern Italy, in the anti-German alliance with the Pataria movement in northern Italy and, above all, in the introduction of a law which gave the cardinals exclusive rights concerning the election of a new pope. Election to the papacy Pope Gregory VII