The Roman Empire (Latin: Imperium Rōmānum, Classical Latin: [ɪmˈpɛ. ri. ũː roːˈmaː. nũː]; Koine and Medieval Greek: Βασιλεία τῶν Ῥωμαίων, tr. Basileia tōn Rhōmaiōn; Italian: Impero romano) was the post-Roman Republic period of the ancient Roman civilization. It had a government headed by emperors and large territorial holdings around the Mediterranean Sea in Europe, North Africa, and West Asia. From the constitutional reforms of Augustus to the crisis of the third century, the Empire was a principate ruled from the city of Rome (27 BC - 285 AD). The Roman Empire was then divided between a Western Roman Empire, based in Milan and later Ravenna, and an Eastern Roman Empire, based in Nicomedia and later Constantinople, and it was ruled by multiple emperors (with the exception of the sole rule of Constantine I between 324 and 337, and Theodosius I between 392 and 395).