Thanks for pointing out the timeline of the books! I think that debunks my last theory but got me thinking!
The letter was Addressed to HOID
Here is what could have happened
The person who wrote the letter killed Rayse and became Odium. After thousands of years Odium has corrupted the writter of the letter, and he now is as bad as Rayse was. Hoid is now here to stop his friend. The 17th shard are members that seek to protect shardbearers from being destroyed (or something similiar) and now hunt Hoid.
TIMELINE:
1) Rayse holding Odium killed Skai and Aona
2) The WoK Letter is written to Hoid
3) The writer of the letter kills Rayse and takes Odium's power for himself
4) Elantris events
5) Way Of King events (Hoid seeks to confront the writer of the letter who now posseses Odium)
WHY I think this makes sense.
The letter sounds like the events in Elantris had just happened, but we know Elantris was thousands of years before the events of the WoK. The letter is written by someone determined to stop Rayse, but from what we see of Hoid he seems like someone who doesn't like interfering with things. I need to look up the quote later but he tells Kaladin that he is here to "See an Old Friend, but has been putting it off". From the letter, the writer said he never liked Rayse, so I am not sure why he would reference Rayse as a friend, but it makes perfect sense for Hoid to reference the writer like that. There is also the question as to why the desolations stopped happening for so long of a time which is answered by this theory.
http://stormlightarchive.wikia.com/wiki/The_Way_of_Kings's_Epigraph_Letter#cite_note-2
Old friend, I hope this missive finds you well. Though, as you are now essentially immortal, I would guess that wellness on your part is something of a given.[1] I realize that you are probably still angry. That is pleasant to know. Much as your perpetual health, I have come to rely upon your dissatisfaction with me. It is one of the cosmere’s great constants, I should think.[2] Let me first assure you that the element is quite safe. I have found a good home for it. I protect its safety like I protect my own skin, you might say.[3] You do not agree with my quest. I understand that, so much as it is possible to understand someone with whom I disagree so completely.[4] Might I be quite frank? Before, you asked why I was so concerned. It is for the following reason:[5]Ati was once a kind and generous man, and you saw what became of him. Rayse, on the other hand, was among the most loathsome, crafty, and dangerous individuals I had ever met.[6] He holds the most frightening and terrible of all of the Shards. Ponder on that for a time, you old reptile, and tell me if your insistence on nonintervention holds firm. Because I assure you, Rayse will not be similarly inhibited.[7] One need only look at the aftermath of his brief visit to Sel to see proof of what I say.[8] In case you have turned a blind eye to that disaster, know that Aona and Skai are both dead, and that which they held has been Splintered. Presumably to prevent anyone from rising up to challenge Rayse.[9] You have accused me of arrogance in my quest. You have accused me of perpetuating my grudge against Rayse and Bavadin. Both accusations are true.[10] Neither point makes the things I have written to you here untrue.[11] I am being chased. Your friends of the Seventeenth Shard, I suspect. I believe they’re still lost, following a false trail I left for them. They’ll be happier that way. I doubt they have any inkling what to do with me should they actually catch me.[12] If anything I have said makes a glimmer of sense to you, I trust that you’ll call them off. Or maybe you could astound me and ask them to do something productive for once.[13] For I have never been dedicated to a more important purpose, and the very pillars of the sky will shake with the results of our war here. I ask again. Support me. Do not stand aside and let disaster consume more lives. I’ve never begged you for something before, old friend. I do so now.[14]
Edited by tipbruley, 12 January 2012 - 09:47 AM.










