Galla Placidia of Constantinople/Istanbul (AD 392-450)
Galla Placidia was the daughter of Theodosius I by his second wife. She was kidnapped by the barbarian Goths when Rome fell in 410, and remained a prisoner until she married the brother of a Gothic king. After his death, Galla married a prominent general. After he died in 425, she became the mother of the new emperor Valentinian, who was just six years old. As a result, she was a co-ruler of the western Roman empire for a decade. In her powerful role, she strongly promoted Nicene orthodox Christianity and opposed all forms of Monophysite (#5) teaching. She died in 450.