Dacia Aureliana was a province in the eastern half of the Roman Empire established by Roman Emperor Aurelian in the territory of former Moesia Superior after his evacuation of Dacia Traiana beyond the Danube in 271. Between 271/275 and 285, it occupied most of what is today northwestern Bulgaria and eastern Serbia. Its capital was in Serdica (modern Sofia).
The Emperor Diocletian's tetrarchy reorganization of the empire divided Dacia Aureliana in two provinces, both part of the civil diocese of Moesia(e), under the eastern Caesar (junior emperor), whose 'quarter' became the Praetorian prefecture of Illyricum. :
In the fourth century reform (also splitting Italy in two while separating Egypt from Oriens and Macedonia from Moeasiae as new dioceses), these two “Dacias” along with Dardania, Moesia Prima, and Prevalitana constituted the Civil diocese of Dacia.
- Grumeza, Ion: Dacia: Land of Transylvania, Cornerstone of Ancient Eastern Europe; Hamilton Books, 2009, Lanham and Plymouth; ISBN 978-0-7618-4465-5
- Westermann (publisher), Grosser Atlas zur Weltgeschichte