 After the death of his father in 421, Valentinian followed his mother and his sister (Justa Grata Honoria) to Constantinople, when court intrigue saw Galla Placidia forced to flee from her half-brother, Emperor Honorius, and the young Valentinian went to live at the court of his cousin Theodosius II.In 423, Honorius died, and the usurper Joannes took power in Rome.To counter this threat to his power, Theodosius belatedly recognised Valentinian's father as "Augustus" and nominated the 5-year-old Valentinian "Caesar" of the West in October 23, 424.