Roman Emperor (Late Empire)

The office of Roman Emperor underwent significant turbulence in the fourth and fifth centuries, particularly under the period of the Dominate. In the West, where the fall of the Western Roman Empire was underway, its holders became puppets of a succession of barbarian kings. In the East, it began to assume trappings.

Arbogast, Valentinian II’s general-in-chief, murdered him in May 392, and replaced him with a puppet Emperor, Eugenius, a former rhetorician. Eugenius was overthrown two years later by Theodosius I (see below), Valentinian II’s brother-in-law.

Much as the Valentinian dynasty was loosely connected to the Constantinian dynasty by marriage, the Theodosian dynasty was loosely connected to the Valentinian; the first Theodosian Emperor, Theodosius I (historically known as "the Great") was son-in-law of Valentinian I. Although he was a Hispano-Roman of military background, like Valentinian, he was no "Barracks Emperor"; he was lawfully and voluntarily elevated to the purple in the East by the reigning Emperor Gratian, his half-brother-in-law, on January 19, 379. He abolished paganism entirely and made Christianity the official religion of the Empire in 391, overthrew Arbogast and his puppet Emperor, Eugenius, in the West in 394, and was the last Emperor to rule both East and West.

After Theodosius's death in 395, the Empire was permanently divided into East and West by his 17-year-old and 10-year-old sons, Arcadius and Honorius, respectively.

By the time the Visigoths under their king Alaric entered Italy and sacked Rome in 410 – the first time a foreign army had set foot in Rome since 390 BC, some 800 years earlier – Rome had ceased to be capital of the Empire either in East or West (the capital in the East was Nicomedia from 286 to 330, and Constantinople from 330 onward; in the West it was Milan from 286 to 402, and Ravenna from 402 onward); indeed, by that point in history, the Bishop of Rome was one of the few senior Ecclesiastical or Imperial officials in the Roman Empire to actually reside in Rome.

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