Faustus of Byzantium was an Armenian historian of the 5th century. Faustus' History of the Armenians exists in four "books", beginning with Book 3 ("Beginning") and ending with Book 6 ("Ending"), which appears to be due to the work of a later editor of the surviving manuscript. The History describes events from the military, socio-cultural and political life of 4th-century Armenia. Pavstos describes in detail the reigns of Arsaces (Arshak) II and his son Papas (Pap), and portrays the Mamikonians as defenders par excellence of Armenia.
