Marcus Opellius Antoninus Diadumenianus
14 September 208 CE
8 June 218 CE
Diadumenian (Diadumenianus) was born on September 14, 208 CE as Marcus Opellius Antoninus Diadumenianus. He was the son of Emperor Macrinus with whom he co-ruled as Caesar (May 217-218 CE) and as Augustus (218 CE).
According to the incredible “Historia Augusta”, Diadumenian was born on September 19, as he was to share his birthday with the former Emperor Antony Pius. His mother was Empress Nonia Celsa. The Diadumenian was given the name Antoninus to emphasize his connection to the lineage of Marcus Aurelius (the first to do so was Caracalla).
Diadumenian had very little time to use his privileged position, because on May 18, 218 CE Elagabalus was proclaimed emperor by the 3rd Gallic Legion (Legio III Gallica) stationed in Syria at that time. The legion began its march towards Antioch and on June 8, 218 CE. there was a clash between the troops loyal to the emperor and the rebels. In the initial phase of the fight neither side gained an advantage, however, later Macrinus, abandoned by most of the soldiers, fled the battlefield and, disguised as a courier (or a representative of the militia), headed towards Rome. In order to confuse his enemies, he shaved his beard and hair. However, he was recognized by one of the centurions and captured near Chalcedonia. Then he was taken to Antioch, where he was also executed in Cappadocia. The Diadumenian was sent to the Parthian site but was captured near the city of Zeugma, and he too was killed before he crossed the border.