Sergius III Murdered Two Predecessors, and Fathered an Illegitimate Child Who Went on to Become a Pope
One of the Middle Ages’ more controversial Popes, Sergius III (circa 860 – 911) was Holy Father from 904 to 911, during a scandalous period of pontifical history. However, even by the standards of scandalous popes, Sergius III stands out for the dubious distinction of being the only pope to have ever had another pope killed. Or to be more accurate, popes, as in plural: Sergius III rose to the papacy by killing his two immediate predecessors, popes Leo V and his successor, Christopher.
Rome and Central Italy in the days of Sergius III were marked by feudal violence and near anarchy, as aristocratic factions warred with each other. The Papacy in particular was one of the most sought after prizes, and the rivals fought bitterly to seize the Holy See and make use of its spiritual, economic, and military resources in their quarrels.
Sergius was born into an aristocratic Roman family, and his connections secured him a rapid rise through the clerical ranks. In the 890s, Sergius was a member of an aristocratic faction that opposed Pope Formosus’ candidate for Holy Roman Emperor, and backed a rival instead. So to get him out of Rome, Formosus made Sergius a bishop and packed him off to oversee his see.
He returned to Rome after Formosus’ death in 896, when his successor had the deceased pope’s corpse dug up, tried, and convicted. All of Formosus’ acts as pope were declared null and void. When the papal throne became vacant soon thereafter, Sergius got himself elected pope in 898 by an aristocratic faction, but another faction elected a rival pope, John IX.
The rival had the backing of the Holy Roman Emperor, so his election stuck, and Sergius was forced to flee Rome. There followed a period of turmoil that saw the election of other rival Popes, until 903, when an antipope named Christopher drove the sitting Pope Leo V out of Rome. Sergius returned to Rome at the head of an army, and seized the city and both competing Popes.
Sergius then ordered Christopher and Leo V strangled, and had himself appointed Pope Sergius III in 904. The controversy surrounding Sergius III does not end with the murder of his predecessors. He also shacked up with a certain Marozia, the daughter of Theophylact, Count of Tuscalum, a powerful ally who helped Sergius expand his territory. He fathered an illegitimate son upon her, who grew up to become Pope John XI.