Pannonia Secunda comprised parts of present-day Serbia, Croatia, and Bosnia and Herzegovina.

Notably, several Roman emperors were born in or near this city, highlighting its significance in the empire's history.

In 314 AD, a pivotal battle took place between two rival claimants to the imperial throne, Constantine the Great and Licinius, in the province of Pannonia Secunda, near the town of Cibalae.

Despite being outnumbered, with an army of 20,000 men against Licinius' 35,000, Constantine emerged victorious after a fierce battle that lasted the entire day.

[2] During the 6th century, the territory was contested between the Ostrogoths, Gepids, Langobards, Avars, and the Byzantine Empire.