I can't keep it all straight in my brain batter right now.
Short answers to a few things:
1. There is only one true civil war, and it was an inter-solar-system affair.
2. However, there was a lot of what we'd probably call civil unrest (but on a HEAVY scale) prior to that. Aka, cities being demolished by protesting robots or humans -- or corporations that were "cutting losses."
3. Time dilation is a thing. Humans in AI War have wormhole technology, but you'll notice that isn't present in any of the other games. Wormholes allow for FTL travel, but beyond that everyone else is bound by c. Given that, some of the timescales are long simply because it takes a long freaking time to get anywhere if you don't have a wormhole.
When we're talking galactic traversal, 800 years is next to no time at all, so various theories about Langstrom and so forth are in no way ruled out.