Constantine VIII
Anna was the daughter of Byzantine Emperor Romanos II and the Empress Theophano. She was also the sister of Emperors Basil II Bulgaroktonos (The Bulgar-Slayer) and Constantine VIII. Anna was a "Porphyrogenita", a legitimate daughter born in the special purple chamber of the Byzantine Emperor's Palace. Anna's hand was considered such a prize that some theorize that Vladimir became Christian just to marry her.