Coins bearing the reverse inscriptions IVNO MARTIALIS or its dative form, IVNONI MARTIALI, appear only during the brief reigns of Trebonianus Gallus and his son, Volusian. The meaning of the epithet Martialis has been a subject of scholarly debate. As Joe Sermarini notes at Numiswiki, the title "literally means 'of or belonging to Mars' or 'warlike,' but the depictions of Juno Martialis on the coins are not warlike. The epithet may refer to Juno as the mother of Mars. Or perhaps she is Juno of March - her festival was on 7 March. Perhaps the title refers to her temple in the Campus Martius, the old 'Field of Mars' down by the Tiber. She is sometimes equated with Juno Perusina, as Perugia was where Trebonianus Gallus came from, and as such is sometimes called Juno Martialis Perusina by modern scholars." This coin is an antoninianus of Trebonianus Gallus, dating from 251-253 CE. Trebonianus Gallus, AD 251-253. Roman AR antoninianus, 4.04 g, 19.8 mm, 8 h. Rome, AD 251-253. Obv: IMP CAE C VIB TREB GALLVS AVG, radiate, draped and cuirassed bust, right. Rev: IVNO MARTIALIS, Juno seated left, holding corn ears and scepter. Refs: RIC 35; Cohen 46; RCV --; ERIC II 73. Notes: A version of this coin (RIC 69), struck at an uncertain mint (per Sear; RIC attributes this issue to Milan; CNG postulates Viminacium), bears the shorter obverse legend IMP C C VIB TREB GALLVS AVG. Coins of the Antioch mint (RIC 83; Cohen 47) also bear the shorter obverse legend as well as officina marks in the form of dots or Roman numerals in the exergue on the reverse. Juno is shown enthroned, holding a transverse scepter, and in her extended right hand she has some objects which are not entirely certain. The listing in RIC expresses doubt with a question mark: Sulzer, writing in 1777, described them as spicae, "ears of grain" ... Cohen describes them as épis, also meaning "ears of grain," but notes "Eckhel, au lieu d’épis, a vu des ciseaux" (Eckel, instead of ears, saw scissors), using the Latin forficulam (little scissors) to describe them ... However, if one examines a number of these coins, one finds many which are so unlike shears or scissors as to make that impossible; for example, my coin shows three objects drooping from Juno's hand. Moreover, why would Juno be holding scissors? Even though grain is more typically an attribute of Ceres, not Juno, I think ears of grain are depicted here. Juno Martialis certainly seems to have been important for Trebonianus Gallus and his son, even though she is obscure to us today. In addition to the above type, other coins of Trebonianus Gallus and Volusian bear the dative inscription IVNONI MARTIALI and depict a small round temple or shrine decorated with garlands in which Juno sits, holding a shield, such as on this sestertius of Volusian sold by Auktionen Meister & Sonntag in 2013: You may see a line drawing of this reverse type and read more about it in Stevenson and Smith's The Dictionary of Roman Coins, available online at Forum. So, where was the temple depicted on this coin? The Dictionary of Roman Coins mentions a temple to Juno Martialis in the Forum, but doesn't cite a source for this. As noted in Sermarini's article in Numiswiki, the epithet Martialis suggests such a temple may have stood on the Campus Martius, the Field of Mars where the troops were trained and where there were already three temples to Juno. Alternatively, the epithet may refer to the Campus Martialis, a small area at the foot of the Caelian hill, though there were apparently no permanent structures there. The temple is so consistently rendered on these coins, such as on this breathtaking medallion sold by CNG ... ... that it's hard to believe the structure didn't exist in antiquity. But in fact, apart from these coins and a few others of the same period, there is no evidence of such a temple, or even that a cult of Juno Martialis existed at all. Post anything you feel is relevant!