Gallic Wars
The Gallic Wars were a series of military campaigns waged by the Roman proconsul Julius Caesar against several Gallic tribes. Rome's war against the Gallic tribes lasted from 58 BC to 50 BC and culminated in the decisive Battle of Alesia in 52 BC, in which a complete Roman victory resulted in the expansion of the Roman Republic over the whole of Gaul (mainly present-day France and Belgium). While militarily just as strong as the Romans, the internal division between the Gallic tribes helped ease victory for Caesar, and Vercingetorix's attempt to unite the Gauls against Roman invasion came too late. The wars paved the way for Julius Caesar to become the sole ruler of the Roman Republic.
Tetricus I
During Tetricus' reign, the main threats to the Gallic Empire came from the Roman Empire and Germanic tribes. Tetricus also had to contend with dissent within the army and government. Tetricus was recognized as emperor by all of Gaul — except Gallia Narbonensis, which had been partially reconquered by the Placidianus, a general under Roman emperor Claudius Gothicus — and Brittania. He was not recognized by the province of Hispania, including Hispania Baetica, Lusitania and Hispania Tarraconensis, — which had earlier refused to recognize Victorinus as emperor — along with the city of Argentoratum (modern-day Strasbourg) in Germania; the provinces which did not recognize Tetricus chose instead to recognize Roman Emperor Aurelian, who had been proclaimed emperor in September 270 at Sirmium in Pannonia. By the time of Tetricus' rule, the Germanic tribes had become increasingly aggressive, launching raids across the Rhine and along the coast. Tetricus moved the capital of the Gallic Empire from Colonia to Augusta Treverorum in late 271, in order to guard against the Germanic tribes. Tetricus attacked them with some success, mainly during the early part of his reign, even celebrating a triumph for one of his victories. Later in his reign he was forced to withdraw troops and abandon forts, which allowed the border territories to be pillaged. Later Germanic raids were met with almost no opposition — one penetrated so far into Gallic territory that it reached the Loire. While Aurelian was concentrated upon attacking the Palmyrene Empire, which had broken away from the Roman Empire in 270, under Empress Zenobia, Tetricus was able to recover Gallia Narbonensis and south-eastern parts of Gallia Aquitania. During 273–274, Faustinus, provincial governor of Gallia Belgica, rebelled against Tetricus, however his revolt was swiftly crushed. Around this time, Tetricus also held the "quinquennalia", public games that took place every four years.