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Early life

Diocletian was born in Dalmatia, probably at or near the town of Salona (modern Solin, Croatia), to which he retired later in life. His original name was Diocles (in full, Gaius Valerius Diocles), possibly derived from Dioclea, the name of both his mother and her supposed place of birth. Diocletian's official birthday was 22 December, and his year of birth has been estimated at between 242 and 245 based on a statement that he was aged 68 at death (alongside other evidence). His parents were of low status; Eutropius records "that he is said by most writers to have been the son of a scribe, but by some to have been a freedman of a senator called Anulinus." The first forty years of his life are mostly obscure. Diocletian was considered an Illyricianus (Illyrian) who had been schooled and promoted by Aurelian. The 12th-century Byzantine chronicler Joannes Zonaras states that he was Dux Moesiae, a commander of forces on the lower Danube. The often-unreliable Historia Augusta states that he served in Gaul, but this is not corroborated by other sources and is ignored by modern historians. The first time Diocletian's whereabouts are accurately established was in 282 when the Emperor Carus made him commander of the Protectores domestici, the elite cavalry force directly attached to the Imperial household. This post earned him the honor of a consulship in 283.