 The following year the younger Tetricus was made co-consul, but the Empire grew weak from internal strife, including a mutiny led by the usurper Faustinus.By that time Aurelian had defeated the Palmyrene Empire and had made plans to reconquer the west.He moved into Gaul and defeated Tetricus at the Battle of Châlons in 274; according to some sources, Tetricus offered to surrender in exchange for clemency for him and his son before the battle.