Diocletian - Augustus of Imperium Romanum from 284 to 305
Gaius Aurelius Valerius Diocletianus Augustus, born Diocles, was Roman emperor from 284 to 305.

Born to a family of low status in the Roman province of Dalmatia, Diocletian rose through the ranks of the military to become cavalry commander to the Emperor Carus. After the deaths of Carus and his son Numerian on campaign in Persia, Diocletian was proclaimed emperor. The title was also claimed by Carus' other surviving son, Carinus, but Diocletian defeated him in the Battle of the Margus.

Diocletian's reign stabilized the empire and marks the end of the Crisis of the Third Century. He appointed fellow officer Maximian as Augustus, co-emperor, in 286.

He reigned twenty-one years and then abdicated voluntarily. He lived out his retirement in his palace on the Dalmatian coast, tending to his vegetable gardens.
Diocletian
Emperor Diocletian of the Roman Empire

(1) Diocletian 284-285 AD
Obverse: laureate, draped bust right; A K Γ OYAΛ ΔIOKΛHTIANOC CEB
Reverse: Elpis standing left, holding flower and raising skirt; LA
Ref: Milne 4750; Curtis 1980; Geissen 32...
(2) Diocletian 285-286 AD
Obverse: laureate and cuirassed bust right; A K Γ OYAΛ ΔIOKΛHTIANOC CEB
Reverse: Dikaiosyne (Aequitas) standing half left, holding scales and cornucopia; L_B
Ref: Milne 4770; Curtis 1967; Dattari 56...
(3) Diocletian 290-291 AD
Obverse: laureate head right ΔIOKΛHTI_ANOC CEB
Reverse: Zeus standing half left, wearing chalmys, holding patera and scepter. eagle at feet; L_Z
Ref: Milne 4946; Curtis 2045; BMC Alexan...
(4) Diocletian 297-298 AD
Obverse: IMP C C VAL DIOCLETIAN P F AVG, Laureate bust right
Reverse: GENIO POPVLI ROMANI, Genius standing left, holding patera and cornucopia
Ref: RIC VI 19a
Obverse: IMP C VAL DIOCLETIANVS AVG, cuir. bust with rad. head right
Reverse: HERCVLI CONSERVAT, Hercules standing right, holding lion-skin
Ref: None provided
(6) Diocletian 303 A.D.
AE unit Carthage
Obverse: MP C DIOCLETIANVS PF AVG, radiate, draped and cuirassed bust right.
Reverse: VOT-XX-FK in three lines within wreath. (FK is the mintmark).
Ref: Carthage RIC VI 37a
(7) Diocletian 285 A.D.
Obverse: IMP CC VAL DIOCLETIANVS PF AVG., radiate, draped and cuirassed bust right
Reverse: MARS VICTOR, Mars walking left, holding spear and trophy. Mintmark VIXXIT
Ref: RIC V239
(8) Diocletian 288 A.D.
Obverse: IMP C VAL DIOCLETIANVS AVG, radiate cuirassed bust right
Reverse: IOVI CONSERVAT, Jupiter standing left, holding thunderbolt and sceptre.
Ref: RIC V 225
(9) Diocletian c. 295-299 AD
Obverse: radiate, draped and cuirassed bust right; IMP C C VAL DIOCLETIANVS P F AVG
Reverse: Diocletian standing right, holding parazonium, receiving Victory on globe from Jupiter standing left holding long scepter; CONCORDIA MI_LITVM / KΓ
Ref: RIC VI Cyzicus 16a
(10) Diocletian 297-299 AD
Obverse: laureate head right; IMP C C VAL DIOCLETIANVS P F AVG
Reverse: Genius standing left, pouring out patera and holding cornucopia; GENIO POPV_LI ROMANI / KΓ
Ref: RIC VI Cyzicus 12a
(11) Diocletian 285-286 AD
Obverse: radiate and cuirassed bust right; IMP DIOCLE_TIANVS AVG
Reverse: Jupiter standing half left, wearing chalmys, holding thunderbolt and long scepter; IOVI CONSER_VAT AVGG / XXIΓ
Ref: RIC V-2 162 Rome
(12) Diocletian 284 AD
BL Antoninianus Tripolis
Obverse: radiate, draped and cuirassed bust right; IMP C C VAL DIOCLETIANVS P F AVG
Reverse: Diocletian right receiving Victory on globe, holding parazonium; Jupiter left giving Victory on globe, holding long scepter; IOVI CONSERVATOR_I AVG / TR / XXI•
Ref: RIC V 328
(13) Diocletian 305-307 AD
Obverse: laureate bust right wearing imperial mantle, holding olive branch and mappa; D N DIOCLETIANO BEATISSIMO SEN AVG
Reverse: Quies standing left extending hand against Providentia who is holding scepter and branch; PROVIDENTIA DEORVM QVIES AVGG / T_F / PLG
Ref: RIC VI 200a var. (obv. legend-BAEAT...
(14) Diocletian 294 AD
Obverse: laureate head right; DIOCLETI_ANVS AVG
Reverse: tetrarchs wearing military dress, sacrificing over tripod in front of turreted enclosure with gate; VIRTVS__MILITVM / A
Ref: RIC VI 40a; RSC 516g
(15) Diocletian c. AD 296-303
Obverse: IMP C DIOCLETIANVS P F AVG, laureate and cuirassed bust right
Reverse: GENIO POPV-LI ROMANI, Genius standing left, holding patera and cornucopiae
Ref: CT 2.01.003 (10); RIC 6a & 16A; cf....
(16) Diocletian 298-299 AD
Obverse: laureate, cuirassed bust right; IMP DIOCLETIANVS P AVG
Reverse: Genius standing left, holding patera and cornucopia, modius on head, chalmys over shoulder; GENIO POPV_LI ROMANI / A _ * / TR
Ref: RIC VI Trier 292a
(17) Diocletian 285-293 AD
Obverse: radiate, draped and cuirassed bust right from behind; IMP C C VAL DIOCLETIANVS AVG
Reverse: Diocletian standing right, holding parazonium, receiving Victory on globe from Jupiter standing left, holding Victory on globe and long scepter; CONCORDIA MILITVM • / B / XXI•
Ref: RIC V-2 306
(18) Diocletian 297-298 AD
Obverse: IMP C C VAL DIOCLETIANVS P F AVG, Head of Diocletian facing right, wearing laurel wreath
Reverse: GENIO POPVLI ROMANI, Genius standing facing left, pouring libation from patera and holding cornucopia; HTB in exergue
Ref: RIC VI Heraclea 19a