Tetradrachm, Ecbatana circa 164-161, AR 27 mm, 16.71 g. Diademed and draped bust of Timarchus r., wearing crested Boeotian helmet. Rev. [BAΣΙΛΕΩΣ] MEΓAΛOY – TIMAPXΟΥ Dioscuri galloping r., each holding spear and palm branch. Houghton, RN 1979, p. 214, fig. A (this obverse die). Le Rider, Suse, pl. LXV, 5-6 (this obverse die). SC 1589.
Of the highest rarity, apparently only the fourth tetradrachm known of this ruler.
A very interesting portrait struck on a narrow flan, minor area of weakness on
reverse, otherwise very fine

Ex CNG sale 123, 2023, 214.
The unexpected death of Antiochus IV Epiphanes at the end of 164 BC sent shockwaves through the Seleucid Empire. His successor in Antioch was the weak child king Antiochus V who was a puppet of the minister Lysias, it was unclear whether Demetrius I might be released from his captivity in Rome, and the Parthian Empire still threatened the eastern borders of the empire. Under these confused circumstances, Timarchus of Miletus, who had been appointed satrap of Media by the dead Antiochus IV, decided to revolt and claim the royal title for himself in the East. Media seems to have quickly recognised him as a new king and he expanded his kingdom to include Babylonia as well. By 161 BC, Timarchus was certainly in control of the Seleucid capital at Seleucia on the Tigris and had been recognised by the Roman Senate. Nevertheless, after escaping from Italy, Demetrius I consolidated his power in Syria and immediately marched against the Median usurper. In the spring of 161 BC, the two kings joined in battle at Babylonia and Timarchus was killed, thus ending his brief independent Median kingdom. Unfortunately, the instability caused by his revolt was to have a lasting impact on Media and the eastern Seleucid Empire. In 148/7 BC, shortly after the death of Demetrius I, Mithradates I, the king of the Parthian Empire, overran Media and by 141 BC also occupied Seleucia on the Tigris. The silver coinage of Timarchus is exceedingly rare today because following his defeat, Demetrius I took great pains to pull it out of circulation and overstrike it with his own types. Timarchus' tetradrachm types reveal the strong influence of the neighbouring Bactrian kingdom of Eucratides I (c. 171-145 BC). Just as on the coinage of Eucratides I, here Timarchus appears draped and wearing a crested Boeotian cavalry helmet, although it lacks the addition of a bull's horn and ear regularly included on the helmet of the Bactrian king. The reverse type also follows the Eucratidean model in depicting the charging Dioscuri and according Timarchus the title of "Great King." This title was originally used by the Achaemenid Persian kings and may have been used by Timarchus to appeal to the Iranian constituents of his kingdom.