The Roman Empire
The Roman Empire was the post-Republican period of ancient Rome, consisting of large territorial holdings around the Mediterranean sea in Europe, North Africa and West Asia ruled by emperors. From the accession of Caesar Augustus to the military anarchy of the third century, it was a principate with Italy as metropole of the provinces and its city of Rome as sole capital (27 BC – 286 AD). The Roman Empire was then ruled by multiple emperors and divided into a Western Roman Empire, based in Milan and later Ravenna, and an Eastern Roman Empire, based in Nicomedia and later Constantinople. Rome remained the nominal capital of both parts until 476 AD, when it sent the imperial insignia to Constantinople (Byzantium in Ancient Greek) following the capture of Ravenna by the barbarians of Odoacer and the subsequent deposition of Romulus Augustus. The fall of the Western Roman Empire to Germanic kings, along with the hellenization of the Eastern Roman Empire into the Byzantine Empire, is conventionally used to mark the end of Ancient Rome and the beginning of the Middle Ages.