Description

Pannonia was an ancient province of the Roman Empire bounded north and east by the Danube, coterminous westward with Noricum and upper Italy, and southward with Dalmatia and upper Moesia. Pannonia was located over the territory of the present-day western Hungary, eastern Austria, northern Croatia, north-western Serbia, northern Slovenia, western Slovakia and northern Bosnia and Herzegovina.

Galerius (Gaius Galerius Valerius Maximianus Augustus) was Roman Emperor from 305 to 311 (293-305 as Caesar under Diocletian, 305–311 as Augustus alongside Constantius until 306, then Severus until 307 then Constantine from 307 to 308 then Licinius from 308). During his reign he campaigned, aided by Diocletian, against the Sassanid Empire, sacking their capital Ctesiphon in 299. He also campaigned across the Danube against the Carpi, defeating them in 297 and 300. Although he was a staunch opponent of Christianity, Galerius ended the Diocletianic Persecution when he issued an edict of toleration in 311.