Antoninianus — Diocletian — Concordia Militum

Obverse: Radiate, draped, cuirassed bust right

Reverse: CONCORDIA MILITVM ("the harmony of the soldiers"), Jupiter handing emperor a Victory on a globe

Mass: 2.95 g

Diameter: 21 mm

The reverse type CONCORDIA MILITVM presents the emperor receiving a small Victory figure standing on a globe from Jupiter, the supreme Roman god and divine guarantor of imperial authority. This imagery emphasizes the loyalty and unity between the emperor and the army, with Jupiter's gift symbolizing divine approval of military success and legitimate rule. The type became one of the most important military messages of the late third century, when emperors relied heavily on army support to maintain power.

Diocletian ruled the Roman Empire from AD 284 to 305 and transformed the imperial system through the creation of the Tetrarchy, establishing a more structured division of power among multiple emperors to improve stability and administration. The antoninianus, originally introduced as a silver double-denarius, had by Diocletian's early reign become a heavily debased bronze coin with a thin silver coating. Issues featuring CONCORDIA MILITVM reflected the importance of securing the army's loyalty during a period of repeated civil wars and presented the emperor as ruling with both military strength and divine support.