Watch List notes:

Trajan. AD 98-117. Æ Sestertius (34mm, 21.85 g, 6h). Rome mint. Struck AD 116-117. Laureate and draped bust right / Trajan seated left on sella castrensis set on daïs, presenting Parthamaspates to Parthia kneeling right; to right of Trajan, prefect standing left. RIC II.1 667; Woytek 594v-21/594v-1 (for obv./rev. dies); Banti 96. Brown and green patina, light roughness, metal flaws in obverse field. Good VF.

Parthian interference in Armenia prompted Trajan to declare war against their king Osroes I in 114. He quickly re-established Roman control of Armenia, forced the submission of Osrhoene, and in 116 took Mesopotamia by defeating Osroes I. Rather than pursuing the Parthians into Iran, Trajan set up a pro-Roman Parthian "buffer state" in Mesopotamia under a puppet-king Parthamaspates.