It looks impressive so far. Really it does.

If you're placing battles, I assume you're using your terrain map to decide where to place them? Because battles often tend to cluster around around strongholds, passes, good open ground, things like that. Most historico-political maps I've seen tend to depict fewer battles and focus more on the major ones. Just as an example, two maps of Alexander's campaign: one and two. Now, it's entirely your choice how many battles to depict, but if you're depicting that many over just 50 years or so, you might think about emphasizing the 5-7 REALLY BIG ONES with maybe a larger symbol and text than the other 20 big, bloody and ultimately not *that* big ones.

What else ... the big blue swords. I just find their colour way too vivid (the crossed scimitar symbols are probably too vivid too, but I'm RG colourblind, so they don't look so vivid to me). Would a pale outline around a darker sword maybe look better? Perhaps placed under the political colour layer? That way it would still be distinctive (more visible than most town symbols) but not so dominant.

Keep 'em coming!