The emperor Jovian (363-364) who reestablished Christianity as the official religion of the Roman Empire was born in Moesia Prima, in Singidunum.

[5] In 382 Roman emperors Theodosius I and Gratian met in Viminacium, the capital of Moesia Prima, during the Gothic Wars.

Major efforts to secure the province were undertaken in the time of Justinian I (527–565) who rebuilt Viminacium and Singidunum around 535, restoring the frontier fortresses to their former military importance.

At the very beginning of the 7th century, Avars and Slavs sacked and burned Singidunum and Viminacium to the ground and the interior of the fallen province Moesia Prima was finally settled by the Slavic Serbs.

[11] The chief towns of Moesia Prima were: Viminacium (sometimes called municipium Aelium; modern Kostolac) and Singidunum (Belgrade).