History of the Roman Empire
Theodosius was the last Emperor who ruled over the whole Empire. After his death in 395, he gave the two halves of the Empire to his two sons Arcadius and Honorius; Arcadius became ruler in the East, with his capital in Constantinople, and Honorius became ruler in the West, with his capital in Milan and later Ravenna. The Roman state would continue to have two different emperors with different seats of power throughout the 5th century, though the Eastern Romans considered themselves to be the only ones who were fully Roman. Latin was used in official writings as much as, if not more than, Greek and the two halves were nominally, culturally and historically, if not politically, the same state.
The Last Legion
The film depicts the coronation of Romulus (and subsequent fall of Rome) as having taken place in 460, while the novel gives the year as 476. In point of fact, coronations were not invented until later in the Roman Empire (in the Byzantine period). Historically, Romulus was a usurper proclaimed by his father in 475. It is believed he was born in 460. Romulus' reign was never recognised as emperor except by his father's troops. The emperors of the East continued to regard Julius Nepos, who had fled Italy and reestablished himself in Dalmatia in the face of a rebellion by Orestes, as the legitimate Western Emperor. Romulus was Emperor for ten months, not a single day as in the film.