The sophistication of Roman siege warfare. There is an entrenched enemy. Caesar's legions build miles of fortification to surround and starve out the enemy. Many more enemies come to break the siege. Caesar's legions build second miles long fortification, around the first.
It is a defining moment in Caesar's rise to fame and infamy, laying the groundwork for his eventual emperorship. Without this victory and Caesar's popular support, the history of Rome may have been very different.
There is a noble sacrifice by the Gallic general, Vercingetorix. Realizing the imminent defeat, he suggests to his people that they kill him or surrender him as a bargaining chip to receive lenience from the conquering Caesar. He does this knowing that the Roman tradition is to march defeated generals through the streets of Rome before ritually killing them. Turns out he got to be imprisoned for years before that "honor".
These are the three things that stood out most to me.
"laying the groundwork for his eventual emperorship".
Worth pointing out that Julius Caesar was never emperor and its difficult to say that he really aspired to such a position. Yes, he was dictator for life but Sulla had fairly recently been appointed dictator with no time limit applied so that wasn't without precedent. Working out what could have happened of he hadn't been assassinated is difficult. Did he take on many of the trappings of a king? Yes. Did he seem to try and avoid that same perception, such as with the crown at Lupercalia? Also yes. Whatever he was though, he certainly was not emperor.
True, but you could say similar things about his successor Augustus. He was outwardly modest and merely referred to himself as "First Citizen", not dictator. But for all practical purposes he was an emperor that ruled for decades.
There was a whole PR strategy related to this that went on for centuries. Many of the rulers after Julius Caesar talked about restoring power to senate and/or the citizens, and downplayed their own immense power, without actually doing much of anything to reduce it.
That said, it's certainly possible that Julius Caesar could have followed a similar path to Sulla. He very well might have had every intention of relinquishing power after a certain point.
From what I understand one big difference between Caesar and Augustus was that Caeser had a fairly sizable domestic agenda with a list of reforms that had been building up and getting frustrated for decades, so it's possible/plausible he was planning to retire once this was accomplished. As far as I know Augustus never had such firm plan aside from consolidating power.
But understanding the domestic politics of the time certainly isn't easy, it's hard enough to understand the internal politics of another country today but throw in a radically different set of political structures and issues.
