Obverse description : Buste lauré et cuirassé de Dioclétien à droite, vu de trois quarts en avant.
Obverse legend : DIOKLETIANOS SEB. (DiokletianoV SebastoV).
Obverse translation : (Dioclétien Auguste).
Reverse legend : L - IA.
Reverse description : Aigle debout à gauche, la tête tournée à droite, tenant une couronne dans son bec ; une étoile dans le champ à gauche.
Reverse translation : (An 11).
(20/11/284-1/05/305) Caius Aurelius Valerius Diocletianus
Diocletian, born in 245 in Dalmatia (Split), is an Illyrian emperor. It takes the purple after removing Aper, the praetorian prefect, stepfather and assassin Numerian, 20 November 284. Struggling against Carin first, last son of Carus, he was defeated at Margus the following year, but was assassinated and Carin Diocletian left alone august. He appoints Maximian, a compatriot, caesar in November 285 and august 1 April 286. It has created a new political regime, the diarchy where two emperors share the military and political power, but is still subject to Maximian Diocletian. Diocletian is placed under the protection Jovian (Jupiter) while Maximian is Herculean gasoline (Hercules). Diocletian spent the first ten years of his reign waging war in the East, while Maximian rest in the West. Diocletian was the first emperor of the Lower Empire, in the words of Gibbons, and founder of the dominat.