Diocletian. AD 284-305. AV Aureus (20mm, 6.51 g, 1h). Cyzicus mint. Struck AD 284-286. DIOCLETIANVS AVGVSTVS, laureate head right / IOVI CO NSERV ATORI AVG, Jupiter Optimus Maximus standing left, holding thunderbolt in right hand and scepter in left; to left at feet, eagle standing left, head and tail right, with wings displayed, holding wreath in beak. RIC VI 298; Depeyrot 14/1; Calicó 4514 . Lustrous. In NGC encapsulation 6559106-005, graded Ch AU, Strike: 5/5, Surface: 5/5. High relief, and perfectly centered. Extremely rare, such that Calicó only has a line drawing of this issue.
From the Willamette Valley Collection. Ex Monaco Collection (Heritage 3094, 19 August 2021), lot 32075; Roma XXI (24 March 2021), lot 717.
Diocletian's tetrarchy ('rule of four') was devised to replace the unstable system of family dynasties which was greatly responsible for the military chaos of the previous century. Central to this system was the founding of two imperial houses, each with an Augustus and Caesar, which would oversee respective portions of the empire. Diocletian modeled the imperial houses upon the Romans' religious pantheon. As the senior Augustus and Caesar, Diocletian and Galerius comprised the 'Jovian' house, and thus enjoyed the protection of Jupiter, the chief deity of the Roman pantheon. This aureus of Diocletian thus depicts Jupiter, Protector of the Augustus. Maximianus and Constantius were the members of the 'Herculian' house, and had the protection of Hercules, who was the right-hand lieutenant to Jupiter.