STEPHEN IX  ., pope from August 1057 to March xo58, succeeded Victor II . (Gebhard of Eichstadt) . His baptismal name was Frederick, and he was a younger brother of Godfrey, duke of Upper Lorraine, marquis of Tuscany (by his marriage with Beatrice, widow of Boniface, marquis of Tuscany) . Frederick, who had been raised to the cardinalate by Leo IX., acted for some time as papal legate at Constantinople, and was with Leo in his unlucky expedition against the Normans . He shared his brother's fortunes, and at one time had to take refuge from Henry III. in Monte Cassino . Five days after the death of Victor II . (who had made him cardinal-priest and abbot of Monte Cassino) he was chosen to succeed him . He showed great zeal in enforcing the Hildebrandine policy as to clerical celibacy, and was planning the expulsion of the Normans from Italy and the elevation of his brother to the imperial throne when he was seized by a severe illness . He died at Florence on the 29th of March 1058 .