The Battle of the Margus or Battle of Margum was fought in July 285 for control of the

Roman Empire The Roman Empire ( la, Imperium Romanum ; grc-gre, Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) was the post-Roman Republic, Republican period of ancient Rome. As a polity, it included large territorial holdings aro ...

between the armies of

Diocletian Diocletian (; la, Gaius Aurelius Valerius Diocletianus, grc, Διοκλητιανός, Diokletianós; c. 242/245 – 311/312), nicknamed ''Iovius'', was Roman emperor from 284 until his abdication in 305. He was born Gaius Valerius Diocles ...

and

Carinus Marcus Aurelius Carinus (died 285) was Roman emperor from 283 to 285. The elder son of emperor Carus, he was first appointed ''Caesar'' and in the beginning of 283 co-emperor of the western portion of the empire by his father. Official accoun ...

in the valley of the Margus River (today

Great Morava The Great Morava ( sr, Велика Морава, Velika Morava, ) is the final section of the Morava ( sr-Cyrl, Морава), a major river system in Serbia. Etymology According to Predrag Komatina from the Institute for Byzantine Studies ...

) in

Moesia Moesia (; Latin: ''Moesia''; el, Μοισία, Moisía) was an ancient region and later Roman province situated in the Balkans south of the Danube River, which included most of the territory of modern eastern Serbia, Kosovo, north-eastern Alb ...

(present day Serbia), probably near the settlement of Margum. The battle proved to be the tipping point that led to the eventual resolution of the

Crisis of the Third Century The Crisis of the Third Century, also known as the Military Anarchy or the Imperial Crisis (AD 235–284), was a period in which the Roman Empire nearly collapsed. The crisis ended due to the military victories of Aurelian and with the ascensio ...

and the return of stability to the Empire. Carinus led the larger force, but the loyalty of his army was definitely questionable. Carinus had allegedly alienated men whose support his success depended upon, including mistreating the

Senate A senate is a deliberative assembly, often the upper house or chamber of a bicameral legislature. The name comes from the ancient Roman Senate (Latin: ''Senatus''), so-called as an assembly of the senior (Latin: ''senex'' meaning "the ...

and its womenfolk and seducing the wives of his officers. The exact circumstances of the battle are in doubt, but it is known for certain that Carinus was killed in the course of the battle, most probably by one of his own officers. Diocletian was then left in sole control of the Roman Empire. The tide of the battle may have tilted to Carinus at first, only to shift in Diocletian's favor after the defection of Carinus'

Praetorian Prefect The praetorian prefect ( la, praefectus praetorio, el, ) was a high office in the Roman Empire. Originating as the commander of the Praetorian Guard, the office gradually acquired extensive legal and administrative functions, with its holders be ...

, Aristobulus. Some scholars suspect that Aristobulus was the officer responsible for the murder of Carinus, an argument that gains credibility in the fact that Diocletian afterward rewarded Aristobulus by confirming him in office as Praetorian Prefect and Consul for the remainder of 285.Southern, P "Roman Empire from Severus to Constantine" (2001), p.135 After his victory, Diocletian administered the oath of loyalty to Carinus' former troops, then turned his attention to the Danube frontier where the

Marcomanni The Marcomanni were a Germanic people * * * that established a powerful kingdom north of the Danube, somewhere near modern Bohemia, during the peak of power of the nearby Roman Empire. According to Tacitus and Strabo, they were Suebian. Origin ...

and

Quadi The Quadi were a Germanic * * * people who lived approximately in the area of modern Moravia in the time of the Roman Empire. The only surviving contemporary reports about the Germanic tribe are those of the Romans, whose empire had its bord ...

were conducting raids across the border.

References

Margus 285 Serbia in the Roman era the Margus 285 280s in the Roman Empire Diocletian Crisis of the Third Century {{AncientRome-battle-stub