 Information about his early life is scarce.According to the Second Life of Saint Naum he grew up in Moesia, which was the Byzantine designation for Bulgaria.According to the hagiography of Clement of Ohrid by Theophylact of Ohrid and some other sources, Naum took part in the historic mission to Great Moravia together with Saints Cyril and Methodius, Clement, Angelarius, Gorazd and other Slavic missionaries in 863.