Caius Pius Esuvius Tetricus was emperor of the Gallic Empire from 270/271 to 273, following the murder of Victorinus. Tetricus, who ruled with his son, Tetricus II, was the last of the Gallic Emperors.
Tetricus was born to a noble family and held the rank of praeses provinciae Aquitaniae at the time of Victorinus' death. Victorinus' mother, Victoria, paid the army heavily to declare Tetricus emperor near Burdigalia (Bordeaux, France), which was approved in Gaul and Britain. Following his appointment, Tetricus repelled Germanic tribes that took advantage of the confusion following the death of Victorinus to invade.
Tetricus installed his capital at Augusta Treverorum (Trier, Germany) and appointed his son Caesar. Tetricus made no attempts to expand the Gallic Empire, other than regaining Aquitania (which had rejoined the Roman empire during the reign of Claudius Gothicus). In 273 Aurelian, the Roman emperor, set out to reconquer the western Roman empire, following his victories in the east. Tetricus took his army southward from Trier to meet Aurelian, who was advancing into northern Gaul. The decisive battle took place near Châlons-sur-Marne, where Tetricus and his son surrendered to Aurelian. According to literary sources, the lives of Tetricus and his son were spared by Aurelian and Tetricus was given the title corrector Lucaniae. Tetricus died at an unknown date living in Italy; he is listed among the Thirty Tyrants in the Historia Augusta.
Due to a secret deal between Aurelian and the Gallic emperor Tetricus I and his son TetricusII, the Gallic army was massacred while the two were allowed to live.
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