Described by Strabo as a small but fertile country between the southeastern Taurus and the Euphrates River in Anatolia, Commagene was nearly always a buffer between much mightier realms and only managed to retain its relatively brief independence, squeezed as it was between Parthia and Rome, by an adroit marriage policy, careful manouvring, and astute alliances, thus exploiting the weaknesses of the great power blocks.
Until the coming of the Romans the abundance of its natural resources of timber and good grazing land made Commagene the richest kingdom in the arid south-east region. Its capital Samosata (Samsat) near Adiyaman, named after Samos I (3rd century BC), commanded a strategic crossing over the Euphrates, and it was this that enabled Ptolemeus, the local ruler, to take advantage in 163 BC of the power struggle between Alexander's successors to make himself king of a small dominion which gradually developed into an independent state.
Its temporary subjection by the Armenians was ended by the Roman Lucullus in 69 BC, and during the reign of Commagene's best remembered ruler, Antiochus I - responsible for the unique site of Nemrut Dag - Pompeii secured the country's independent statehood which was to last until Vespasian absorbed it into the Roman province of Syria in 72 AD.