Pope Sergius IV becomes the 142nd pope, succeeding Pope John XVIII.

Pope Sergius IV 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 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.

Pope John XVIII was the bishop of Rome and nominal ruler of the Papal States from January 1004 to his abdication in July 1009. He wielded little temporal power, ruling during the struggle between John Crescentius and Emperor Henry II for the control of Rome.