Pope Sergius IV

Pope Sergius IV (died 12 May 1012) was the bishop of Rome and nominal ruler of the Papal States from 31 July 1009 to his death. His temporal power was eclipsed by the patrician John II Crescentius. Sergius IV may have called for the expulsion of Muslims from the Holy Land, but this is disputed. Since his time, the practice that the person who has been elected to the office of pope takes on a new name became a tradition.

Source: Wikipedia — https://en.wikipedia.org/wiki/Pope_Sergius_IV