Okay, for people without Lost Empires of Faerun/Grand History of the Realms, a quick rundown of nations that would probably help out.
Aryvandaar: Sun elf ruled large and powerful nation, sees itself as rightful unifier and overlord of the elves for how far along it is compared to everyone else, very tenuous (to possibly not really existant and a thin justification) ties to Miyeritar's ruling houses from their own, been attempting to get Miyeritar to fold into their nation via diplomacy for a while, this has not been working. Secretly the arrogance of the ruling caste of the nation is being egged on by fiendish corruption from within at the hands of a fallen solar that was cast down by Corellon Larethian into the hells, who is the hidden patron of the Vyshaan, the ruling clan of the nation, the Coronal (elf title for their king or queen) comes from it. Canonically speaking after several centuries of war, Corellon Larethian himself proclaims "okay, that's enough, also the Vyshaan have lost their right to rule, also new political structure", the Vyshaan's violent military refusal results in every other remaining nation (the drow have already been cast down at this point) uniting against them and putting them and Aryvandaar down.
Miyeritar: Nation of dark elves in a renaissance of art and magic and the like, under pressure from Aryvandaar to join them. Not actually evil, or Lolth worshipping, or any such thing, certainly at least at the beginning (Elistraee is decently popular there, as deities go), as they get hammered and conquered and despairing, corruption weaves its way in a lil bit, but not really to the point of the other dark elf nation. Some also find secret support and sanctuary in Illefarn instead of such developments. Some of them also form resistance movements within their occupied land. Basically they get blamed for a lot of shit that isn't their fault at all, particularly by the Aryvandaar who are always looking to justify their rolling waves of conquest and then oppressive reigns over conquered peoples. Most of them (which is to say more accurately, such few as survive things like a magical cataclysm Aryvandaar ultimately throws on them after several centuries of conflict) end up being cast down with the rest of the now become the drow, due to sidescatter of the magic that did it in a lot of cases. Speaking of which..
Illythir: Do you like evil? Because this is your other place for it. Parts of the Illythiri dark elf noble houses have been toying with stuff like Ghaundaur worship well before the crown wars, if keeping it a secret, doing things like trying to secretly goad wars between their neighbour nations (various green and moon elf countries) for no real good reason. When said wars start, this nation, ultimately egged on by corruption efforts from Lolth that some would argue was not exactly a huge leap for these fellows, the Illythir basically use it as an excuse for general rampage and power mongering, branching out from attacks in the Aryvandaar's direction as far as anyone remotely tied to them to burning various elf kingdoms wholesale. Actual burning, they destroy whole swaths of forest and everyone in em. An effort by several elf kingdoms together to invade and try and break Illythir off their corruption will ultimately fail. Illythir, compared to the being secretly evil parts of Aryvandaar, ultimately starts openly rocking out as what they are, being more blatant about their atrocities, and ultimately gets rumbled by the rest of elfdom and cursed and cast down to the underdark to become the drow.
Shantel Othreier: A moon elf ruled nation being pressured by Aryvandaar to join them, currently via diplomacy. The people there have a similar ongoing "stfu" response. One of the bigger, more powerful nations, and actually powerful enough that they manage to hold out against being ultimately attacked by Aryvandaar (once they conquer Miyeritar) for quite some time (though they do slowly lose territory to them), they're even able to endure the loss of forces they contributed to the war against the Illythiri, being one of the leaders of that effort. It takes the probable assassination of their pretty buff Coronal for Aryvandaar to finally conquer them. Ultimately they're one of the nations the Illythiri later rampage on and destroy (having been conquered helped that out)
Ardeep: A moon elf nation, initially vassals of Shantel Othreier, when that nation gets conquered as the crown wars go on, they have to go it on their own, but surprisingly manage to maintain their freedom from Aryvandaar for quite some time, with again, leader death making for their ultimately being conquered. They seem a bit more green elf influenced-ish in their overall shtick.
THeanytaar: A green elf kingdom (so, you know, semi tribal, especially forest dwelling, that kind of thing), especially ancient, one of the big nations of the alliance against Illythir and their rampages in the aforementioned invasion to break them off their corruption. Its failure ultimately contributes to this particular nation getting wiped the hell out by the Illythiri.
Eiellūr: Same deal as the above kingdom, green elves, quite old, part of that alliance. They fell though due to traitors from within looking to appease the Illythiri.
Ilefarn: The great sun elf nation of the furthest west (and probably made such in a bit of a retcon so as to go "see? not all the sun elves were awful"), powerful enough that when they basically declared themselves neutral, no one especially tried to challenge them, or that political position for almost the entire crown wars (note almost, they do finally suffer from it near the end). Their biggest involvements canonically were giving clandestine support to Miyeritar, which largely took the shape of smuggling communities of them into their own nation to give them sanctuary as the crown wars got worse. They also at one point basically spent 10 years straight mass praying to the gods for the end of the Crown Wars.
Syņrpiir: A nation where sun and moon elves came together to rule, you know, together. So that's all noble and near singular and stuff. So obviously if we need to establish the whoa evil of the Ilythiri, guess which nation they're going to wipe out first as the Crown Wars roll on. This is part of what goads an alliance of a few other nations to take a run at the Illythiri in the midst of all the Aryvandaar trying to conquer people stuff.
Orishaar: A moon elf nation that, shockingly, had a good relationship with Aryvandaar, to the point of being an independant trading partner (yeah, this probably would have changed as Aryvandaar fully comitted as hardcore as possible to Conquer! Everything! as the crown wars rolled on). Which was seen by the Illythiri as a good enough excuse to include these people on a "let's wipe out smaller elf nations" hit parade, as one of their thin justifications was revenge against Aryvandaar before they just openly rolled with "and you know, also Lolth and demon lords and stuff said it would be fun".
Keltormir: A nation where green and moon elves came together to build and rule a nation and the result was badasses. A nation that managed to hold out against the Illythiri rampage (and Aryvandaar, and whoever really. The Keltomir national motto is probably some kind of elven variant of "Come at me bro") , despite having lost troops in that whole earlier invasion of it. A nation founded by dragonslayers. A nation that furthermore survived the crown wars without having been conquered at one point (whereas even Ilefarn near the end was subjugated for a bit), though they did lose territory as it went on.
I can do a quick little capsule summary of the different elf types as well if anyone would find that helpful. But otherwise very rough and not super accurate.. the sun elves are like a copper skinned Noldor- advanced, potent, capable of great grandeur, inclined to build big grand societies, but also arrogant and domineering, the moon elves are the closest to your standard fantasy elves as you might get, the green elves are a more tribalized and especially embracing of the forest sorts of elves (think like.. kinda sorta the Mirkwood elves to again dip into Tolkien), the dark elves are kinda sorta like the moon elves, but with darker skin