The Battle of Nicaea was fought in 193 between the forces of Septimius Severus and his eastern rival, Pescennius Niger.

Severus defeated his rival, and ended his bid for the Roman Empire the next year at Issus.

The Praetorian Guards then held an auction for the throne, which was won by Didius Julianus, who became emperor.

The auction was unpopular, and Septimius Severus, commander of the Pannonian legions, and Pescennius Niger, the governor of Syria (as well as Clodius Albinus, the governor of Britain) all claimed the Roman imperial throne after the auction.

Severus had previously defeated Pescennius at the Battle of Cyzicus (193) in Asia Minor.