Introduction
The Khoramabad museum in Lorestan Province, which is one of the outstanding museums of Iran, and which is situated in the ancient satrap of the Medes, is home to a number of coins of Alexander as well as Seleucid and Parthian kings. It also houses a small number of tetradrachma coins of the Bactrian Greeks: a silver coin of Antimachus I (175-165 BC) with bust wearing flat Kausia/Poseidon standing, weighing 11 grams, and 43 silver coins of Eucratides I with helmeted bust/Dioscuri type whose weights range from 10.80 grams to 14 grams, as well as one of Heliocles I (145-130 BC) Bust/standing Zeus type. How did these coins come to be in Iran?
Historical background
When they established a dynasty in the time of Arsaces I (238-211 BC), the Parthians (238 BC-224 AD) were still confined to a local territory. The death of Eucratides, a Bactrian contemporary of the Parthian Mithradates I, paved the way for the Parthian kings to expand their power, a goal accomplished towards the end of the reign of Mithradates I (171 to 138/7 BC). Having captured Demetrius, a Seleucid king, and taken him to Hyrcania, Mithradates I put an end to the political presence of the Seleucids among the Medes. Thus the Parthians emerged from a local kingdom into an imperial power.
Phraates (138-127 BC), a successor of Mithradates I, enlisted the support of Scythian for a sudden victory over the Seleucid Antiochus VII, a successor of Demetrius (Justin, Book XLII). The Scythians arrived very late (possibly due to their military preoccupations with the Greeks of Bactria (Reference BivarBivar 1993: 38)). Although coming late, they asked the Parthian king to pay them or engage them as mercenaries. The Parthian king refused and attacked them. But Phraates was killed, and the Scythians occupied the vast Parthian territory, extending their power to Mesopotamia (Reference BivarBivar 1993).
Before surfacing in Phraates' reign, the Scythians had been obsessed with their struggles with the Greeks of Bactria in the north-eastern region. They devastated much of northern Afghanistan and then became neighbours to Parthia. In Merv they issued prototype tetradrachmas of Eucratides until the Parthians caused them to settle in Sistan (Mitchener 1978: 277-8). In Balkh, the Scythians imitated the coins of the son and successor of Eucratides, Heliocles I, until the Greeks were expelled from Bactria and settled in southern Hindu Kush (Mitchener 1978: 277-8).
Discussion
The Ecbatana mint issued drachmas of the Seleucids and Parthians continuously. The presence of the monolingual Greek Bactrian legends cannot just be due to an extension of commercial activities along the trade routes between the Medes satrap in the west and Bactria in the east. Neither can it be explained as a temporary political relationship with Parthia, for the earlier issues of this dynasty are absent in the trade routes and in the Parthian territories. Indeed the mere presence of tetradrachma cannot be used to imply commercial relations between the two kingdoms.
These coins, which were coins of the Greeks of Bactria, were present in those territories captured from them by the Scythians. When the Scythians also occupied Parthia, their circulation in trade routes followed. Subsequently the Greeks were forced to migrate south to the Hindu Kush, and the Scythians were made to settle in the south-west of Iran by Mithradates II, who also restored the Parthian supremacy. At that point, the circulation of Greek coins of Bactria in northern Iran ceased.
