Born about 980, he became Pope under the name Nicholas II in December 1058. Having banished the antipope Benedict X, Nicholas II carried out numerous reforms, including the Lateran Council, according to which the election of the new pope was the prerogative of the cardinals, to the detriment of the temporal sphere. Certainly a decisive step was the agreement made in Menfi with Robert Guiscard, who became Duke of Apulia, Calabria and Sicily in 1059. He died in Florence in 1061.
