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Caesar begins procuring more troops because of his expectation that more uprisings will come about in Gaul. The gathering of these soldiers has a two fold effect of strengthening Caesar's Units and intimidating the Gauls.
The Treveri continue to persuade the Germans to join them in a pact against Caesar, and Caesar learns of this development. He also suspects that other tribes such as the Nervii, Aduatuci, Menapii, and some Germans are in on it. So, Caesar prepares for his campaign.
He attacks the Nervii and captures lots of hostages as well as livestock, providing these plunders to his troops whom he orders to burn the fields. Caesar predicts that further rebellions will arise, however. Caesar's advance scares the Senones and Carnutes into providing hostages, whom Caesar uses as leverage to prevent rebellions while he deals with Ambiorix and the Treveri. He splits up his forces between himself, Gaius Fabius, and Marcus Crassus for this endeavor.
Labeinus, another Roman general leads troops who rout the Treveri in a tactical masterclass. He camps across the river from them with his troops, and then pretends to be leading the troops away on the premise that they are unable to cross the river. This was done simply to lure the Treveri in, however. So, one the Treveri start moving into the river as they attempt their attack, Labeinus turns his troops around and attacks.
Caesar then contextualizes some intertribal conflicts that he shakes up simply through his presence as he moves into Gaul. Power shifts from the Aedui to the Sequani due to conflicts, and then finally the Remi, who were friends of Caesar. The Aedui regained power, becoming once against he most powerful tribe with the Remi second.
You've probably noticed the apparent gap in chapters here, but don't fear, you've already read these chapters (13-20) back in Unit 2. If you'd like to review them, check out our guides
here. Alright, let's get back into it.
After providing various descriptions of the Gauls, Caesar contrasts those descriptions with ones of the Germans. He explains that they do not have Druids or sacrifices, and they only believe in visible gods (pertaining to thinks like the sun). Their people are fairly nomadic and quite war-like. They also have a very structured social system with wartime leaders and such.
Caesar's focus then shifts back to his military campaigns. He explains his decisions regarding not pursuing the Suebi into the forest, and he prepares to lead his troops once spring comes around to attack Ambiorix. Caesar sends his Cavalry ahead, and they almost catch Ambiorix. Further groups of soldiers are sent after Ambiorix as the quest continues.
During this pursuit, though, German forces move into Gaul and begin plundering all over the place in regions unoccupied by the Romans. They even try to to corner as small Roman force in Aduataca. A camp headed by Cicero is attacked by Germans while some are gathering grain and others are sleeping, putting them at a severe disadvantage in the battle. Commotion stirs up and Caesar describes the event like a movie scene, recalling quotes from various soldiers about their concerns, fears, beliefs, etc. He even describes the response of Publius Sextius Baculus, a Roman leader who goes and fights despite battling illness and being unable to eat for five days. He fight valiantly before being severely wounded and fainting.
The soldiers gathering food hear the commotion of the battle, but many are unsure of what is going on. Luckily for them, Gaius Trebonius returns and aids the Roman cause, leading the Germans to avoid storming the camp and retreat. Nevertheless, the soldier's fears are not quelled until Caesar soon returns. Of course, this detail is a subtle indication by Caesar of his own greatness and power as a general. He makes sure to include these small complements for himself throughout his work and write in the third person so that they appear more objective.
Caesar assesses the situation upon his arrival and concludes that luck was a pivotal factor for both sides of the conflict, but he does denounce the poor strategy of going out to retrieve food in the manner that the soldiers did because it left many vulnerable. He also notes that even though the goal of the Germans was the plunder some cities and potentially take out Ambiorix, they were closer to doing the opposite by attacking the Romans.
With Caesar having returned and assessed the situation, he leads his soldiers as they destroy towns and fields on their quest to find and take out Ambiorix, who continually is able to survive Caesar's pursuits. By the end of the book, Caesar is still unable to catch Ambiorix, but he does make some final progress on this quest.