Battle of Naissus

In 268 — or 269, by another dating — a coalition of Goths (Greuthungi and Thervingi), Gepids and Peucini, again led by the Heruli, invaded the empire across the Black Sea and the Danube. The Historia Augusta speaks of 320,000 warriors and 2,000 ships, Zosimus of the same 320,000 men on 6,000 ships — figures modern historians regard as gross exaggerations (the Historia Augusta is itself an unreliable source), though they show the scale of the invasion. The invaders besieged Thessalonica and Cassandreia but turned north when the emperor approached. Near Naissus the Romans lured them into an ambush by a feigned flight, and the cavalry, probably led by Aurelian, delivered the decisive attack; according to Zosimus, more than 50,000 of them were killed.

The survivors fell back towards Macedonia behind their wagon laager. Harried by the cavalry and short of food, they were surrounded in the Haemus mountains, where an epidemic broke out among them, and eventually surrendered; prisoners were enrolled in the army or settled on the land as coloni. With crises in the East and the West, the victory brought only temporary relief. Claudius took the title Gothicus Maximus but died of plague at Sirmium in 270. Who commanded at Naissus is disputed: most modern historians credit Claudius II, while Andreas Alföldi and others attributed the victory to Gallienus, murdered in 268. All the ancient accounts go back mainly to the lost history of Dexippus.