List of Famous people named Sergius

Sergius of Radonezh, also known as Sergiy Radonezhsky, Serge of Radonezh and Sergius of Moscow, was a spiritual leader and monastic reformer of medieval Russia. Together with Seraphim of Sarov, he is one of the Russian Orthodox Church's most highly venerated saints.

Patriarch Sergius I was the 12th Patriarch of Moscow and all the Rus', from September 8, 1943 until his death. He was also the de facto head of the Russian Orthodox Church in 1925–1943, firstly as deputy Patriarchal locum tenens (1925–1937) subsequently as Patriarchal locum tenens (1937–1943).

Pope Sergius I was the bishop of Rome from 15 December 687, to his death, and is revered as a saint by the Roman Catholic church. He was elected at a time when two rivals, Paschal and Theodore, were locked in dispute about which of them should become pope. His papacy was dominated by his response to the Quinisext Council, the canons of which he steadfastly refused to accept. Thereupon Emperor Justinian II ordered Sergius' arrest, but the Roman people and the Italian militia of the exarch of Ravenna refused to allow the exarch to bring Sergius to Constantinople.

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.

Pope Sergius II was the bishop of Rome and ruler of the Papal States from January 844 to his death. Sergius II's pontificate saw the Arab raid against Rome as well as the city's redevelopment.

Pope Sergius III was the bishop of Rome and nominal ruler of the Papal States from 29 January 904 to his death. He was pope during a period of violence and disorder in central Italy, when warring aristocratic factions sought to use the material and military resources of the papacy. Because Sergius III had reputedly ordered the murder of his two immediate predecessors, Leo V and Christopher, and allegedly fathered an illegitimate son who later became pope, John XI, his pontificate has been variously described as "dismal and disgraceful", and "efficient and ruthless".

Saint Sergius of Valaam was a Greek monk and wonderworker credited with bringing Orthodox Christianity to Karelian and Finnish people. Conflicting church traditions place him possibly as early as the 10th century or as late as the 14th. His feast day is celebrated on June 28.