Very enjoyable! Naturally very Obra Dinn/Golden Idol-esque, but I found the conclusions here generally more intuitive, only making a single mistake (I didn't realize that Taal died before the war, implying that she couldn't be the vaiteth, it had to be Lemal)
The choice of pure HTML/JS is excellent, as it leads to very fast load times here and nice quality-of-life features like copy-paste for free.
Some nitpicks that are understandable for a jam game:
(1) Having two different search functions, where one is limited to only three results, but the other can't discover new documents, gets awkward at the end of the game when you have almost every document, so you can't safely switch to the other search function with all results.
(2) As far as I read the rules of succession, an heir must have a beirvet or be betrothed at the point of the current cyne's death to be considered a 'suitable heir'. It seems to me that the 'true' line of succession is technically broken: Lemot's last words implies that Sartina doesn't have a beirvet, and by omission probably isn't betrothed; her obituary also seems to confirm that her tabeir is after Nolveth's cynvei, that is, after Lemot's death. Is the implication that even Lemot was kept in the dark about Sartina's betrothal?