Marcus Cassianius Latinius Postumus
AD? ~ 269
Marcus Cassianius Latinius Postumus, of unknown birth date is believed to have been a citizen of Gaul and through hard work, rose through the military ranks and eventually becoming governor of either Germania Inferior or Superior.
Postumus along with several military commanders and Saloninus, the son of ruling emperor Gallienus, were left to protect the Rhine. While under attack Postumus was declared emperor by his army and went on to invade the city of Cologne where he murdered Saloninus.
Gaul, Spain, Germany and Britain all recognised Postumus as emperor. He set up his own empire with Cologne as the capital along with its own senate. In 263 Gallienus sought to eliminate Postumus but returned home to Rome seriously wounded. One of Gallienus' generals who was in command of Milan pledged his allegiance to Postumus. To march on to Rome to claim a formal title as emperor Postumus would have needed the support of this city, but when the general was besieged by Gallienus, Postumus failed to support him.
In 268, one of Postumus’ top military leaders Laelianus challenged his position when he was declared emperor by his troops while in Mainz. Postumus was quick to react, but after successfully capturing the city of Mainz and killing Laelianus, his own troops turned on him and killed him.