Answer
Pulcheria was a daughter of the Eastern Roman Emperor Theodosius II and his wife Aelia Eudocia. She was betrothed to the Western Roman Emperor Valentinian III in 437, but the engagement was broken off when Valentinian was killed in 455. Pulcheria then married Marcian, a general in the Roman army, on 25 November 450. Marcian became Emperor in 457, and he and Pulcheria ruled jointly until Marcian's death in 457.