Pope Stephen IX

Pope Stephen IX (c. 1020 – 29 March 1058) was Pope from 3 August 1057 to 29 March 1058.

His baptismal name was Frederick of Lorraine (French: Frédéric de Lorraine), and he was a younger brother of Godfrey III, Duke of Lower Lorraine, who, as Margrave of Tuscany (by his marriage to Beatrice of Bar, widow of Boniface III of Tuscany), played a prominent part in the politics of the period.

Frederick, who had been raised to the cardinalate by Pope Leo IX, for some time discharged the function of papal legate at Constantinople. He was with Leo IX in his expedition against the Normans and at one time had to take refuge from Emperor Henry II in Monte Cassino. Five days after the death of Pope Victor II (who had made him cardinal-priest and abbot of Monte Cassino) he was chosen to succeed him as Pope Stephen IX. He enforced the policies of the Gregorian Reform as to clerical celibacy, was planning for 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, from which he only partially and temporarily recovered. Stephen IX died at Florence on 29 March 1058 and is considered by the current-day Roman Catholic Church to have been succeeded by Pope Nicholas II, though others consider his successor to be Pope Benedict X, officially regarded as an antipope.