The homonoia between two cities of the Greek world was the proclamation of an "agreement" or commonality of interests, almost like the "sister-city" arrangements between modern cities. While the Leagues of Greek cities were primarily military alliances, a homonoia was a union based on political, economic and religious connections. The cities of Asia Minor preserved this tradition under the Romans, with an extensive interlinked system of alliances. The earliest coins marking these agreements appear under Domitian, but the majority come later, dating from the Severan period through the end of provincial coinage in the late 3rd century AD. Ephesus seems to have been the most sought after party to these unions, a popularity undoubtedly associated with its status as the principal cult center of Artemis. Pergamum was the political nexus of Asia Minor, and also appears frequently among the unions. The eminence of Cyzicus is surely due to its traditional role as the economic powerhouse of the Propontis, dominating the trade routes between Asia, Greece, and the Black Sea littoral. Perinthus is a mere 75 kilometers away, directly north on the Thracian shore of the Propontis, and was likely a frequent trading partner of Cyzicus. THRACE, Perinthus.,i> Gordian III
. 238-244 AD. Æ Medallion (41mm, 36.19 gm, 2h). Homonoia with Cyzicus in Mysia. AVT K M ANT ΓΟΡΔΙΑΝOC AVΓ, laureate and cuirassed bust right, cuirass decorated with aegis / ΠΕΡΙΝΘΙΩΝ ΔIC ΝΕΩΚΟΡΩΝ OMONOIA KVZIKHNΩN, Kore of Cyzicus standing right, holding sceptre in left hand, and Tyche of Perinthus standing left, holding cornucopiae in left hand, both holding pateras in their right hands out of which they sacrifice over flaming altar between them. Franke & Nollé 1721; BMC Thrace -; SNG Copenhagen -;
Second known specimen of this rare medallion, much superior to the cited example.