EMPIRE and Persians under Cyrus, in 3468, and closed with the death of Darius Codomannus in 3674. The Grecian empire lasted only during the reign of Alexander the Great, beginning in the year of the world 3674, and terminating with the death of this conqueror in 3681, his conquests having been divided amongst his captains. The Roman empire commenced with Julius Cæsar, when he was made perpetual dictator, in the year of the city 708, and of the world 3956, forty-eight years before Christ. The seat of the empire was removed to Byzantium by Constantine, in the year of our Lord 334; and the East and West were then united under the title of the Roman empire, till the Romans proclaimed Charlemagne emperor, in the year 800. From this epoch the East and West formed two separate empires. That of the East, governed by Greek emperors, commenced in the year 302; and being gradually weakened, terminated under Constantine Palæologus in 1453. The western empire was afterwards known by the appellation of the empire, or German empire. Antiquaries distinguish between the medals of the Upper and Lower Empire. The curious only value those of the Upper Empire, which commenced with Cæsar or Augustus, and ended in the year of Christ 260. The Lower Empire comprehended near 1200 years, reckoning downwards till the destruction of Constantinople in 1453. Two ages, or periods, of the Lower Empire are usually distinguished; the first beginning where the Upper ends, namely, with Aurelian, and terminating with Anastasius, including 200 years; and the second beginning with Anastasius, and ending with the Palæologi, which includes 1000 years.