Just rewatched it after 15 years - gosh! I took a break in watching anime, okay? ;) -, and even by todays' standards, I think, it's a very good one. It was my favorite back then and it is now still.
Yes, the age shows, the art is not as catchy, there are more stills, grand battles portrayed in small perspectives, but still, if you get involved in the world and the story, none of that will matter (the backgrounds, the buildings, the towns, the interiors, the clothes are pretty detailed). It does not have that retro anime look which prevents me rewatching many older shows, the soundtrack is epic and the English dub is acceptable (not as great as English voice talent work these days, but it's ok. You might want to listen this in Japanese.)
So about the story. First of all, Twelve Kingdoms is hardcore fantasy, there is not a single mistep in that. No boobies, no panties, no cute girls (nah, that's not true), no yummy foods, no comedy, no laughing, just blood, struggle and suffering, you can be sure about that. It is compensated by large scale world building, epic storytelling, serious dialogs, catharsis and fulfillment; the ending is one of the greatest I have ever seen, every sentence has its own weight supported by the whole story built up until then.
There is a huge collection of manga behind it and the main arc is about Youko Nakajima's detailed transformation from schoolgirl to queen. It happens in the first 39 episodes, minus those few in the middle which is about the black kirin, Taiki. (Kirins are mythical animals choosing kings and spiritually connecting with them.) Those episodes can be skipped, but you either won't make it that far or will be so involved, that you won't skip those anyway since those episodes add some more details to the world. (Youko is a bit lost in the beginning, but bear with it, she will become a godess in the end.)
What makes it interesting about Youko's journey is first the world which is very detailed, think about historic China, and well thought out with lots of lore. Secondarily and most importantly, the fact that she has to earn the throne twice. Because there is a big difference between getting the title and earning it. First she gets the throne formally and later she becomes worthy of it. "Because nobody is given anything without responsibility and if they were, that would be wrong." as Rakushun points out, who is by far the best character I have ever encountered in any anime or other medium for the matter. (Yes, he is the rat in my avatar and he becomes Youko's best friend and mentor somewhere around episode 6.)
In the second part of Youko's adventure there are two other character arcs, not as big than Youko's, but still interesting and deep, just to shake things up a little, and all these arcs culminate nicely at the end, which is episode 39 in fact. (There are six more episodes after that, but those are forgottable.)
This is my all time favourite anime. Would be nice to see a real life adaptation, but probably would never happen.
