Østromersk kejser 395-408. Søn af Theodosius, broder til Honorius.

• Aquileia II, 394
• Byzantinske Rige, 395-1453

Arcadius (377-408), første østromerske kejser, søn af Theodosius d. Store, fik 395 ved dennes død den østlige del af Romerriget. Han lod sig stadig lede af andre, til sidst af sin hustru Eudoxia, og riget hærgedes af hungersnød og barbarernes indfald. (HK1/1920)

Flavius Arcadius (377/378–May 1, 408) was Roman Emperor in the Eastern half of the Roman Empire from 395 until his death.

Arcadius was the elder son of Theodosius I and Flacilla, and brother of Honorius, who would become a Western Roman Emperor. His father declared him an Augustus in January, 383. His younger brother was also declared an Augustus in 393.

As Emperors, Honorius was under the control of the Romanized Vandal magister militum Flavius Stilicho while Arcadius was dominated by one of his ministers, Rufinus. Stilicho is alleged by some to have wanted control of both emperors, and is supposed to have had Rufinus assassinated by Gothic mercenaries in 395, but definite proof of these allegations is lacking. In any case, Arcadius' new advisor Eutropius simply took Rufinus' place as the power behind the Eastern imperial throne. Arcadius was also dominated by his wife Eudoxia, who convinced her husband to dismiss Eutropius in 399. Eudoxia was strongly opposed by John Chrysostom, the Patriarch of Constantinople, who felt that she had used her family's wealth to gain control over the emperor. Eudoxia used her influence to have Chrysostom deposed in 404, but she died later that year.

Arcadius was dominated for the rest of his rule by Anthemius, the Praetorian Prefect, who made peace with Stilicho in the West. Arcadius himself was more concerned with appearing to be a pious Christian than he was with political or military matters, and he died, only nominally in control of his empire, in 408.