The Seleucid Empire is a Greek-Macedonian state that is created out of the eastern conquests of Alexander the Great.

At the height of its power, it includes central Anatolia, the Levant, Mesopotamia, Persia, today's Turkmenistan, Pamir and parts of Pakistan.The Seleucid Empire is a major center of Hellenistic culture which maintains the preeminence of Greek customs and where a Greek-Macedonian political elite dominates, mostly in the urban areas.

The Greek population of the cities who form the dominant elite are reinforced by emigration from Greece.

Seleucid expansion into Egypt is abruptly halted after decisive defeats at the hands of the Roman army.

Much of the eastern part of the empire is conquered by the Parthians under Mithridates I of Parthia in the mid-2nd century BCE, yet the Seleucid kings continue to rule a rump state from Syria until the invasion by Armenian king Tigranes the Great and their ultimate overthrow by the Roman general Pompey.