Last updated: 4 July 2017
Diocletian - the reforming Augustus
Diocletian (Caius Aurelius Verus Diocletianus) has come down in history as an astute politician, accomplished administrator and a stalwart leader. Upon assuming the Imperium as Augustus in 284 he determined to bring an end to the social and political chaos that had pervaded the Roman Empire for over fifty years by instituting several radical reforms including the institution of a Dyarchical, and subsequently a Tetrarchical, form of government. He was the driving force in reorganizing the entire Imperial Governmental System and reforming the coinage.
The Dyarchy of Diocletian and Maximian Herculius: 285-293
In 285 Diocletian appointed Marcus Aurelius Valerius Maximianus, a close friend and a renowned General like himself, as his Caesar elevating him to co-Augustus the following year. Diocletian emphasized his status as Senior Augustus by adopting Jovius as his Protector-God and assigning Herculius to Maximian. Diocletian subsequently divided the Empire geographically with himself as Augustus of the East and Maximian Herculius as Augustus of the West, thereby instituting a Dyarchy. Diocletian established his headquarters at Nicomedia and Maximian Herculius his at Milan.
Carausius - usurper Augustus of secessionist Britain
The political and military turmoil of the third century spawned numerous external assaults on the Roman Empire. One of these was the incessant seafaring piracy in the waters surrounding the Roman occupied island outpost of Britain. In 286 Maximian Herculius, in his capacity as Dyarch Augustus of the West, designated a highly regarded military commander named Marcus Aurelius Mausaeus Carausius, of Flemish descent, to head a fleet of ships who's mission was to eliminate, or at least severely curtail, this piracy. Carausius had distinguished himself by outstanding leadership and military prowess, especially as a naval "Admiral", in the Gallic campaigns.
Carausius established his operational base at the coastal city of Boulogne (Gesoriacum) in Roman occupied northern Gaul. Carausius did indeed accomplish his mission, but reports of corruption and extortion led Maximian Herculius to dispatch a fleet of ships in order to remove Carausius from command. However, Carausius proved too strong and he repulsed the attack. Carausius subsequently used his continental base to launch an invasion force to occupy and subjugate Britain. Landing in the north, Carausius secured the support of the native Picts and, advancing south, confronted and defeated the forces of the Roman Governor. Having thus conquered the Island, he proclaimed himself Augustus of a Secessionist Britain, becoming an effective and efficient Administrator using the Roman Imperial governmental framework as a model. He maintained control of Boulogne and coastal northern Gaul.
Carausius established his own mints at London (Londinium) and Colchester (Camulodunum - Clausentum) -- "C" Mint -- and across the Channel in Gaul which began to produce coins of distinctive style in gold, silver and bronze.
Carausius attempted to assert his equality with the legitimate Dyarchal Augusti, Diocletian and Maximian Herculius (not accepted by them), by issuing a series of Antoniniani (some in their names) which included the titulature AVGGG (the three Augusti: Diocletian, Maximian Herculius and Carausius) as part of the reverse legend.
RIC V (2), London, Carausius, Antoninianus, No. 335
IMP C CARAVSIVS P AVG ......................................... PAX AVGGG | S .....P | C
RIC V (2), London, Carausius, Antoninianus. No. 5
IMP C DIOCLETIANVS PF AVG ........................ PAX AVGGG | S .....P | MLXXI
RIC V (2), London, Carausius, Antoninianus, No. 34
IMP C MAXIMIANVS PF AVG ........................ PAX AVGGG | S .....P | MLXXI
Institution of the Tetrarchy in 293
In 293 Diocletian finalized the Institution of a Tetrarchy -- government of the Empire by four interacting rulers -- two Augusti assisted by two subordinate Caesars, which each Augustus would personally select. The two Caesars, chosen because of their proven leadership abilities, assisted the Augusti with civil administration and command of the armies. Caius Galerius Valerius Maximianus was chosen by Diocletian to be his Caesar of the East and Flavius Valerius Constantius was chosen by Maximian Herculius be his Caesar of the West.
The first assignment given Constantius by Maximian Herculius was to remove Carausius, the usurper Augustus of secessionist Britain, and restore that former possession to the Empire. Constantius thereupon beseiged and captured Boulogne and then wrested coastal Gaul from Carausius. Constantius now set about planning the invasion, occupation and restoration of secessionist Britain to the Empire. One of the first orders of business for Constantius in 294 was to insure that a supply of reformed aes coinage (folles) - now the commonplace legal tender of the Roman Empire - was available for use not only by his occupying force, but also by the British civilian populace. To that end Constantius established a Mint in Gaul (exact location usually listed as unknown, although some French sources list it as Boulogne), manned by Lugdunese workers, to produce this invasion coinage - unmarked (i.e. without a mint mark) issued in the names of Diocletian & Maximian Herculius as Augusti and Constantius & Galerius Maximian as Caesars.
Allectus - usurper Augustus of secessionist Britain
After an uneasy interregnum Constantius, newly appointed Tetrarch Caesar of the West, in 294 beseiged and captured Boulogne and then wrested coastal Gaul from Carausius. Shortly thereafter Allectus, the chief Minister and associate of Carausius, conspired to assassinate him and thereupon declared himself Augustus of Secessionist Britain.
RIC V (2), London, Allectus, Antoninianus, No. 33
IMP C ALLECTUS P F AVG ............................. PAX AVG ..... S (Pax standing left) A
M L in exergue.
Allectus continued operation of the London and Colchester/Camulodunum/Clausentum (uncertain) mints and coins were issued in his name and bearing his portrait. In addition to the silver washed copper Antoninianus of Carausius, Allectus issued a copper coin of reduced size bearing the letter Q in the exergue which has been interpreted to mean Quinarius
Britain restored to the Roman Empire by Constantius
In 296 Constantius launched a powerful naval invasion force against Britain in two divisions: one led by himself, which sailed from Boulogne and the other led by his Praetorian Prefect, Asclepiodotus, which sailed from the mouth of the river Seine. The mission of Constantius was to remove Allectus from power and restore Britain to the Empire. This mission was accomplished and although Constantius was in overall command of the operation, some historical sources assert it was the force under Asclepiodotus that did most of the fighting on land and in fact it was they who defeated and killed Allectus during the decisive battle. Constantius subsequently entered the city of London to proclaim his conquest as restorer of the eternal light of the Roman Empire: Redditor Lucis Aeternae.
This is a photograph of the reverse of a bronze copy of the famous ten aurei multiple (RIC VOLUME VI, TREVERI, No. 34), the original of which presently resides in the museum at Arras, commemorating the restoration of Britain to the Roman Empire by Constantius in 296. It depicts the personification of Londinium (LON) kneeling and supplicating to Constantius (on horseback) outside of the City Fortification while a galley with Roman soldiers waits on the river Thames. The inscription REDDITOR LVCIS AETERNAE proclaims Constantius as the restorer of the eternal light (of Rome). The Treveri (Trier) mint mark (PTR) is in the exergue.
Bastien records the original (unique) coin as No. 218 in his book on the Arras Hoard and mentions that galvano copies were made and sold by the Paris coin dealer Bourgey. At a weight of 23.0 grams I think the copy depicted here was cast in bronze from one of those galvano copies. There appears to be numerous other copies in circulation in a variety of metals - brass/bronze, silver, gold, gilded copper, etc. Following are obverse and reverse depictions with attribution information:
FL VAL CONSTANTIVS NOBIL CAES ............. REDDITOR LVCIS AETERNAE
LON (right) PTR (exergue)
Abdication of Diocletian and Maximian Herculius
Elevation of Galerius Maximian and Constantius to Augusti
1 May 305
On 1 May 305, Diocletian and Maximian Herculius abdicated to become Seniore (retired) Augusti as planned. Constantius succeeded Maximian Herculius as Augustus of the West and Galerius Maximian succeeded Diocletian as Augustus of the East. Flavius Valerius Severus (Severus) was appointed Caesar of the West by Constantius and Galerius Valerius Maximinus Daia (Maximinus) was appointed Caesar of the East by Galerius.
Death of Constantius 25 July 306
Constantius died at Eboracum (York)
in Britain during a campaign against the warlike tribes
of the North on 25 July 306. Just before he died,
Constantius conferred Imperium on his son, Flavius
Valerius Constantinus (later Constantine the Great).
The army commanded by Constantius wanted Constantine
proclaimed Augustus, however, Galerius Maximian, the
now de-facto senior Augustus, instead proclaimed him
Caesar of the West and elevated Severus to Augustus of
the West in accordance with the rules for
The London Mint continued to operate until 325, mostly under the auspicies of Constantine.