Pelagia (Greek: Πελαγία; d. early 4th century), distinguished as Pelagia of Tarsus and Pelagia the Martyr (Πελαγία ἡ Μάρτυς, Pelagía ē Mártys), is a legendary Christian saint and martyr who lived in Tarsus in Cilicia (southeastern Asia Minor) during the reign of Roman emperor Diocletian. Originally, her feast day was celebrated on October 8, in common with SS Pelagia the Virgin & Pelagia the Harlot, both of Antioch and one or both of whom her story is probably modeled after. In the Roman Catholic Church, the feast was eventually moved to May 4.