When were the Gallic Wars?
143229#0
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.
Gallic Wars
391164#4
Caesar engaged in the Gallic Wars (58–50 BC), which led to his conquest of Gaul beyond Gallia Narbonensis. When the Helvetii, a federation of tribes from what is now Switzerland, planned a migration to the Atlantic coast through Gaul, Caesar went to Geneva and forbade the Helvetii to move into Gaul. While he went to Gallia Cisalpina to collect three other legions, the Helvetii attacked the territories of the Aedui, Ambarri, and Allobroges, three Gallic tribes, which called for Caesar’s help. Caesar and his Gallic allies defeated the Helvetii. The Gallic tribes then asked for Caesar to intervene against an invasion by the Suebi, a Germanic tribe. Caesar defeated the Suebi. In 57 BC he intervened in intra-Gallic conflicts and marched on the Belgae of northern Gaul. From then on he conquered the Gallic peoples one by one. His successes in Gaul brought Caesar political prestige in Rome and great wealth through the spoils of wars and the sale of war captives as slaves.
Battle of Alesia
8824675#10
The "Gallic Wars" were a series of military campaigns waged by the Roman proconsul Julius Caesar against Gallic tribes, lasting from 58 BC to 51 BC. The Romans would also raid Britannia and Germania, but these expeditions never developed into full-scale invasions. The Gallic Wars 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. The wars paved the way for Caesar to become the sole ruler of the Roman Republic.
Celtic warfare
28933941#0
The military campaigns of Julius Caesar constituted both the Gallic War (58 BC-51 BC) and Caesar's civil war (50 BC-45BC) in 59 BC, which had been highly controversial. The Gallic War mainly took place in what is now France. In 55 and 54 BC, he invaded Britain, although he made little headway. The Gallic War ended with complete Roman victory at the Battle of Alesia. This was followed by the civil war, during which time Caesar chased his rivals to Greece, decisively defeating them there. He then went to Egypt, where he defeated the Egyptian pharaoh and put Cleopatra on the throne. He then finished off his Roman opponents in Africa and Hispania. Once his campaigns were over, he served as Roman dictator until his assassination root on March 15, 44 BC. These wars were critically important in the transition of the Roman Republic into the Roman Empire.
Military campaigns of Julius Caesar
22235155#15
In 58 BC Julius Caesar launched the Gallic Wars and had conquered the whole of Gaul by 51 BC. He noted that the Gauls (Celtae) were one of the three primary peoples in the area, along with the Aquitanians and the Belgae. Caesar's motivation for the invasion seems to have been his need for gold to pay off his debts and for a successful military expedition to boost his political career. The people of Gaul could provide him with both. So much gold was looted from Gaul that after the war the price of gold fell by as much as 20%. While they were militarily just as brave as the Romans, the internal division between the Gallic tribes guaranteed an easy victory for Caesar, and Vercingetorix's attempt to unite the Gauls against Roman invasion came too late. After the annexation of Gaul a mixed Gallo-Roman culture began to emerge.
Gauls
867792#47
The Gallic sack led to a long-lasting and profound fear of the Gauls in Rome. In 350 and 349 BC, unspecified Gauls attacked Latium. They were probably marauding raids. On the second occasion, Marcus Valerius Corvus was said to have fought a duel with a Gallic champion. Polybius said that Rome made a peace with the Gauls, who did not return for 30 years. Despite Rome defeating the Senones in the Battle of Sentinum (295) during the Third Samnite War (298-290), popular fear of the Gauls persisted. In 228, 216, and 114 fears of Gallic attacks led to the Romans performing human sacrifices by burying alive a pair of Gauls and a pair of Greeks even though human sacrifice was not a Roman custom. Presumably, that was to avert the danger of Gallic disaster.
Battle of the Allia
391164#19
Alesia proved to be the end of generalized and organized resistance against Caesar's invasion of Gaul and effectively marked the end of the Gallic Wars. In the next year (50 BC) there were mopping-up operations. During the Roman civil wars Gallia was essentially left on its own. Marcus Vipsanius Agrippa became its first governor in 39–38 BC. In 39 BC he settled the Ubians on the west bank of the River Rhine and in 38 BC he suppressed a rebellion in Aquitania. He built a radial network of roads centred on the Gallic capital, Lugdunum (Lyon). Gallia was divided into three Roman provinces; Gallia Aquitania, Gallia Lugdununensis and Gallia Belgica. Only the Arverni kept their independence thanks to their victory against Caesar at the Battle of Gergovia.
Battle of Alesia
22235155#1
The Gauls emerged around the 5th century BC as the bearers of the La Tène culture north of the Alps (spread across the lands between the Seine, Middle Rhine and upper Elbe). By the 4th century BC, they spread over much of what is now France, Belgium, Spain, Portugal, Switzerland, Southern Germany, Austria, the Czech Republic and Slovakia by virtue of controlling the trade routes along the river systems of the Rhône, Seine, Rhine, and Danube, and they quickly expanded into Northern Italy, the Balkans, Transylvania and Galatia. Gaul was never united under a single ruler or government, but the Gallic tribes were 
capable of uniting their forces in large-scale military operations. They reached the peak of their power in the early 3rd century BC.
The rising Roman Republic after the end of the First Punic War increasingly put pressure on the Gallic sphere of influence; the Battle of Telamon of 225 BC heralded a gradual decline of Gallic power over the 2nd century, until the eventual conquest of Gaul in the Gallic Wars of the 50s BC. 
After this, Gaul became a province of the Roman Empire, and the Gauls were ethnically and culturally largely assimilated into Latin (Roman settlers) majority, losing their tribal identities by the end of the 1st century AD.
Gauls
143229#32
Discontent among the subjugated Gauls prompted a major uprising in the winter of 54–53 BC, when the Eburones of north-eastern Gaul rose in arms under their leader Ambiorix. Fifteen Roman cohorts were wiped out at Atuatuca Tungrorum (modern Tongeren in Belgium) and a garrison commanded by Quintus Tullius Cicero narrowly survived after being relieved by Caesar in the nick of time. The rest of 53 BC was occupied with a punitive campaign against the Eburones and their allies, who were said to have been all but exterminated by the Romans.
Gallic Wars
32794#9
At various locations described by Vitruvius, battles and sieges occurred. He is the only source for the siege of Larignum in 56 BC. Of the battlegrounds of the Gallic War there are references to: the siege and massacre of the 40,000 residents at Avaricum in 52 BC; Vercingetorix commented that "the Romans did not conquer by valor nor in the field, but by a kind of art and skill in assault, with which they [Gauls] themselves were unacquainted." The broken siege at Gergovia in 52 BC. The circumvallation and Battle of Alesia in 52 BC; the women and children of the encircled city were evicted to conserve food, where they starved to death between the opposing walls of the defenders and besiegers. And the siege of Uxellodunum in 51 BC. These are all sieges of large Gallic "oppida". Of the sites involved in Caesar's civil war, we find the Siege of Massilia in 49 BC, the Battle of Dyrrhachium of 48 BC (modern Albania), the Battle of Pharsalus in 48 BC (Hellas – Greece), the Battle of Zela of 47 BC (modern Turkey) and the Battle of Thapsus in 46 BC in Caesar's African campaign. A legion that fits the same sequence of locations is the Legio VI Ferrata, of which "ballista" would be an auxiliary unit.
Vitruvius