The life of Galla Placidia was so adventurous that it is quite surprising that nobody has made a movie out of it yet. Placidia was the granddaughter of the Roman emperor Valentinian I, the daughter of his successor Theodosius I, the half sister of emperor Honorius and the mother of the later emperor Valentinian III (425-455). As such, she was regent of the Western Roman Empire from 425 to 437.
Here, we see Galla Placidia on a tremissis issued by her son Valentinian III. The reverse depicts a cross, symbolizing Galla Placidia's Christian faith.