Otacilia Severa, wife of Philip I (Marcus Julius Philippus), who reigned 244-249.
Roman provincial Æ 24.5 mm, 11.18 g.
Mesopotamia, Nisibis, AD 244-249.
Obv: MAP ΩTAKIΛ CЄOYHPAN CЄB,
(Marcia Otacillia Severa Sebasta)
diademed and draped bust right, on crescent.
Rev: IOY CЄΠ KOΛΩ NЄCIBI MHT,
(Julia Septimia Colonia Nisibis Metropolis)
[This "Julia" is a family name for Philip.]
Tetrastyle temple containing statue of city goddess seated facing; above her head, ram (Aries) leaping right, head turned back; below, river god Mygdonius swimming right.
References: Sear Greek Imperial Coins 4065. BMC 27. SNG Copenhagen 244. RPC VIII "unassigned; ID 2575."
Emperors from Macrinus to Gordian III also issued coins at Nisibis, but they are scarcer. Here is a large coin of Gordian III and Tranquillina with a design also issued for Singara. (For Singara the reverse legend has "CINΓAPA" instead of "ΝƐϹΙΒΙ".) It is likely coins of Singara and Nisibis were struck at the same mint.
Gordian III (238-244) and Tranquillina
32 mm.
The obverse legend begins at 8:30:
ΑΥΤΟΚ Κ Μ ΑΝΤ ΓΟΡΔΙΑΝΟΝ ϹΑΒ ΤΡΑΝΚΥΛΛΙΝΑ ϹƐΒ
Imperator Caesar Marcus Antonius Gordianus (et) Tranquillina Augusta
ϹƐΠ ΚΟΛΟΝ ΝƐϹΙΒΙ ΜΗΤ
Septimia Colonia Nisibis Metropolis
City goddess seated left on rocks, holding ears of grain, ram left above, river god (Mygdonius) swimming left below.
History. Nisibis was made a Roman colony under Septimius Severus (Hence the title ϹƐΠ for "Septimia" seen on some of its coins), but Roman provincial coins did not begin until Macrinus (217-218). They are scarce through Gordian III (238-244). Then they are common under emperor Philip (244-249) and his family, Philip II and Otacilia Severa--the last Romans to issue coins from Nisibis. Nisibis was probably lost to the Sasanians c. 250-252 which explains why Roman provincial coinage from Mesopotamia ceased then. However, Mesopotamia was still being fought over as late as the time of Julian II (360-363) before it was terminally ceded to the Sasanaians upon the retreat of Jovian (363-364) after the death of Julian.
A.H.M. Jones, in The Cities of the Eastern Roman Provinces, writes "... Lucius Verus annexed Mesopotamia. The Parthians did not acquiesce in the loss of the province, and further campaigns were required under Septimius Severus, Caracalla, and Macrinus to maintain the conquests of Verus. Then, early in the third century [AD 224], the Sassanian dynasty replaced the effete Arsacids [Parthians] and renewed the struggle for Mesopotamia with greater efficiency. Successive campaigns were fought by Severus Alexander, Gordian III, Philip, Valerian, Odenathus, and Carus.
"...Severus was certainly the founder of Septimia Rhesaina and Septimia Nisibis, which later took the additional title Julia [seen on coins as "IOVΛI"] in honor of Philip."
Jones continues "... Under Diocletian the Persian wars continued. ... Julian, after brilliant initial successes, was disastrously defeated and his successor Jovian (363-364) signed an ignominious peace whereby not only the greater part of Diocletian's conquests but [also] Nisibus and Singara, which had been in Roman hands since the days of Severus and perhaps Verus, were surrendered to the Persians."
To the right: A 27 mm drachm of Shapur I (240-270), the Sasanian King who fought against Gordian III and Philip.
Obverse: His bust right with mural crown distinguishing him.
Reverse: Fire altar with attendants on either side.
Reference: Sellwood 14, Göbl 23.
The (very good) book by Dodgeon and Lieu translates all the primary sources that mention conflicts between Rome and the Persia. Zonaras wrote that Carrhae and Nisibis had been taken in the reign of Maximinus (235-238). About Gordian III the Scriptores Historia Augustae says, "From there [Thrace] he marched through Syria to Antioch, which was then in the possession of the Persians. There he fought and won repeated battles and drove out Shapur, the king of the Persians, the successor of Artaxerxes. After this he recovered Antioch, Carrhae, and Nisibis, all of which had been included in the Persian Empire. " ... "Still in existence is an oration of Gordian to the Senate wherein, while writing of his deeds, he gives boundless thanks to his prefect and father-in-law, Timesitheus." SHA says of Timestheus, "but such Felicity could not endure. For as most say, all through the plotting of Phillip, who was made prefect of the guard after him, or as others say because of a disease, Timestheus died, leaving the Roman state as his heir." Philip undermined Gordian with the soldiers and finally had Gordian murdered. He made peace with the Persians (Sasanians) at the cost of 500,000 denarii. In c.250-252 Nisibis was catured by the Sasanians, which explains the lack of later Roman provincial coins from the city.
Nisibis was recaptured under Odaenathus of Palmyra late in the time of Gallienus, but by then provincial coins were uncommon and not issued that far east. Aurelian recovered it for the central empire by defeating Palmyra. Shapur II failed to take Nisibis under Constantius II after three long and brutal seiges. But, after the death of Julian II (360-363) in battle in Mesopotamia it was ceded to the Sasanians under Shapur II by Jovian as part of the price of a safe retreat.
References.
Coin sources: BMC Greek, Mesopotamia. 1988. Of course, some coins of Nisibis are in SNGs (Danish, 12 pieces in volume VII. Righetti, 8 pieces. Lewis, 0 pieces. Hunterian, 9 pieces), but SNGs are all without commentary.
Butcher, Kevin. Roman Provincial Coins. A wonderful thin book which I love, but it has very little about Nisibis (on page 104).
Roman Provincial Coinage on-line: https://rpc.ashmus.ox.ac.uk/search/browse?volume_id=15&number=&city_id=667®ion_id=&province_id=&subprovince_id=&reign_id=&obverse_inscription_simplified=&reverse_inscription_simplified=&obverse_design=&reverse_design=&metal_id=&weight_min=&weight_max=&diameter_min=&diameter_max=&format=
Books.
Dodgeon, Michael and Samuel Lieu, editors. The Roman Eastern Frontier and the Persian Wars, AD 226-363, A Documentary History. 1191. 431 page paperback of translated sources and commentary. Arranged chronologically. Very interesting. Read what ancient authors said about the conflicts, and learn when they wrote and what we now think about what they wrote. This book has many more mentions of Nisibis than the other books below.
The next three are all very good (and large) books on the eastern regions of the Roman empire, but Nisibis is treated on very few pages.
Ball, Warwick. Rome in the East. 2001
Butcher, Kevin. Roman Syria and the Near East. 2003
Millar, Fergus. The Roman Near East: 31 BC - AD 337. 1993:
Internet.
Roman Provincial Coinage volume VIII on-line: https://rpc.ashmus.ox.ac.uk/volumes
with serach results here:
https://rpc.ashmus.ox.ac.uk/search/browse?volume_id=15&number=&city_id=667®ion_id=&province_id=&subprovince_id=&issue_id=&reign_id=&obverse_inscription_simplified=&reverse_inscription_simplified=&obverse_design=&reverse_design=&metal_id=&weight_min=&weight_max=&diameter_min=&diameter_max=&format=
Wikipedia pages:
Nusayban https://en.wikipedia.org/wiki/Nusaybin
Roman-Persian Wars https://en.wikipedia.org/wiki/Roman%E2%80%93Persian_Wars
The Battle of Nisibis (217) https://en.wikipedia.org/wiki/Battle_of_Nisibis_(217)
The siege of Nisibis (252) https://en.wikipedia.org/wiki/Siege_of_Nisibis_(252)
Other web pages:
Strange War Tactics—The Sieges of Nisibis (337-350) https://thehistorianshut.com/2016/11/19/strange-war-tactics-the-sieges-of-nisibis-337-350-ce/
Go to the Table of Contents for this entire educational site.
Roman Coins of Nisibis—a mini-theme. 
Philip I, 244-249
Philip II, 244-249