The Battle of Mons Seleucus was fought in 353 between the forces of the legitimate Roman emperor Constantius II and the forces of the usurper Magnentius. Constantius' forces were victorious, and Magnentius later committed suicide.

It took place in La Bâtie-Montsaléon in today's department Hautes-Alpes, Southern France.

The battle

Despite victory at Pavia in 351 after his defeat at Mursa Major, the usurper Flavius Magnus Magnentius was pursued back to Gaul by Emperor Constantius II, who later took an army west from Milan to finally deal with his rival. In south-eastern France at Mons Seleucus (department of Hautes-Alpes, near modern Gap), Magnentius suffered a decisive defeat. He fled northwest to Lugdunum, where he took his own life by falling on his sword. Following the suppression of Magnentius' rebellion, Constantius commanded an investigation be made to find his followers. The most notorious agent in this search was the cruel Paulus Catena ("the chain"). Many people were tortured and killed.

The aftermath

Constantius II became the undisputed Emperor of the Roman Empire. Coordinates: 44°27′35.3″N 5°44′10.5″E / 44.459806°N 5.736250°E / 44.459806; 5.736250


Byzantine Battles. (n.d.). Retrieved May 24, 2016, from Byzantine Battles: Battle of Mons Seleucus