Originally from Paphlagonia, Theodora was of Armenian aristocratic descent. The names of her parents were preserved in Theophanes Continuatus, the continuation of the chronicle started by Theophanes the Confessor. They were Marinos, a drungarios, and Theoktiste Phlorina. Genealogies attribute Mamikonian ancestry to Marinos; he is an alleged son of Artavazd Mamikonian, who was head of the House in the 770s.