Elected 31 Aug., 257, martyred at Rome, 6 Aug., 258. His origin is unknown. The "Liber Pontificalis" says that he was a Greek by birth, but this is probably a mistake, originating from the false assumption that he was identical with a Greek philosopher of the same name, who was the author of the so-called "Sentences" of Xystus. During the pontificate of his predecessor, St. Stephen, a sharp dispute had arisen between Rome and the African and Asiatic Churches, concerning the rebaptism of heretics, which had threatened to end in a complete rupture between Rome and the Churches of Africa and Asia Minor (see SAINT CYPRIAN OF CARTHAGE). Sixtus II, whom Pontius (Vita Cyprian, cap. xiv) styles a good and peaceful priest (bonus et pacificus sacerdos), was more conciliatory than St. Stephen and restored friendly relations with these Churches, though, like his predecessor, he upheld the Roman usage of not rebaptizing heretics.