Castra Singidunum
About
Legio IV Flavia Felix was raised by Vespasian in 70 CE from the cadre of the disbanded IV Macedonica, and was moved to Singidunum (modern Belgrade) by Domitian in 86 CE to shore up the Danube frontier after the Dacian invasion that destroyed V Alaudae. It remained Singidunum's garrison through 117 CE and for centuries after (into the 5th century).
What happened here
A legionary fortress holds five thousand men and is laid out to the same plan everywhere, so a transferred soldier knows his way around on the first day. Two main streets cross at the headquarters building, where the standards and the pay chest are kept in a sunken strongroom under guard. Around it: the commander's house with a courtyard garden, granaries raised on stone piers, a hospital, workshops, and long barrack blocks divided into rooms for eight men who cook and mess together. Training is daily, and building work is constant — soldiers make their own bricks, tiles and boots. A civilian town grows against the walls, with bars, traders and the unofficial families of men who are not legally allowed to marry.
In ancient writing
- Priscus of Panium, History (Fragments) fragment on the 441 CE Hunnic invasion
Priscus, a 5th-century Byzantine historian, names Singidunum among the Danube cities sacked by Attila's Huns in 441 CE, alongside Viminacium and Margus — a genuine literary description, though written centuries after 117 CE.
Sources
Roman Maps shows the empire frozen at 11 August 117 CE, the day Trajan died — its moment of greatest territorial extent. Explore the full map →