Here's the best I can do at what each of the dahns includes, without spoilers. Stuff in italics is unconfirmed but is reasonable to guess based on the information we have from the books and Brandon.
- 1st Dahn: The King and the King's direct heir.
- 2nd Dahn: Highprinces, their direct heirs, and the King's direct heir*.
- 3rd Dahn: Generals?, Highlords, and the non-inheriting children of 1st and 2nd dahn lighteyes.
- 4th Dahn: Battalionlords, Citylords, Shardbearers, and other mid-ranked nobles.
- 5th Dahn: Companylords?, along with lower-ranked nobles.
- 6th Dahn: Captainlords, along with the lowest-ranked nobles and landholders?
- 7th Dahn: Lower-ranking landless officers, along with higher-ranking (or very wealthy) landless lighteyes?
- 8th Dahn: Soldiers, along with high-ranking (or moderately wealthy) landless lighteyes?
- 9th Dahn: Landless lighteyes with some wealth, like merchants and master craftsmen.
- 10th Dahn: "Tenners", essentially any lighteyes who has to work for a living.
I'm very impressed by this list. You did a great job. Note that only the king is first Dahn under the Alethi system, however. His heir is second, until crowned. Sixth Dahn, as you've identified, is the "landed" cutoff--if you have land, even a little, you're at least Sixth Dahn.
If you were of a specific dahn (say, seventh) but were elevated by something unusual (say, you got appointed to an appointment that would raise you above this) your children will often be elevated to a rank just beneath you. So, for instance, if a tenner got a shard, he'd immediately be elevated to fourth, and his family would likely be elevated to fifth.
The only thing I'd offer a warning on is that sometimes, people shortcut "Captainlord" to just "Captain" which drives Peter crazy, and so it can be hard to pick out rank from title.
That's interesting... so, is the dahn system new since Alethkar was unified? Or was it modified once they got a king? Or was it always this way, and there just used to not be someone at the 1st Dahn?
Kings existed in other places, and had existed in Alethkar before. (Dahn is a Vorin cultural ideal, not just Alethi.) So the system is not new, but for many years, the Alethi refused to accept a king. (Following the division of the kingdom among the Sunmaker's sons.)
Oooooooh... fascinating. So, this implies that before Gavilar unified Alethkar, King Taravangian and the King of Jah Keved would both have been First Dahn, while the highest-ranked ten people in Alethkar were only Second Dahn. Interesting. In the interests of adding a few more names to the list of "known people of the First Dahn" on the Coppermind, would you be willing to confirm if King Taravangian (let's say at the start of the Way of Kings to avoid spoilers) was First Dahn?
Traditionally, the monarchs of city-states (like Kharbranth, Bavland, and at some points Silnasen) do not claim the first dahn. There have been leaders of New Natanan who have, same with Herdaz. Depends on how much they want to aggravate the Alethi.
Unification era, there'd be two people of the first dahn: The queen of Thaylenah and the king of Jah Keved. Non-vorin monarchs in the west would be treated like first dahn, sometimes, depending on the situation.
Did we know that Thaylenah is currently ruled by a Queen, or is this a small tidbit you have just given us?
I'm not sure if I've mentioned it or not, honestly. Queen Fen. You'll get to meet her soon. Note that Thaylenah is kind of a plutocracy, with merchant councils holding a lot of power, which changes its dynamic a little when compared to Alethi or Jah Keved.
I see you may have sneakily included an explanation for the 4th/5th dahn thing I noticed in a certain father-daughter duo. I promise not to read too much into it....
Note that getting a Shardblade isn't the only reason someone could be elevated, and isn't the only reason why children might not be the same dahn as their parent. Most of it has to do with titles, and who inherits, and that sort of thing. The answer is probably more boring than you're hoping.
Not sure if this is entering RAFO territory, but are highprince candidates (that is, people who can be elevated to highprince status if the post is empty) only people from the 3rd dahn? Or can a 4th dahn also be elevated to highprince, for example?
Highprince is a tricky one, as the definition of "highprince" is a person who can convince others to call him by the title. I guess that's the same for all of them, but as highprinces tend to be near the top of the pecking order, it's more about military than anything else.
Gavilar was 4th dahn before becoming highprince, for example. His branch of the Kholin family wasn't considered a prime contender for the highprince throne--until he took it for himself.
His branch of the Kholin family? Does this imply there are other branches of the Kholin family? Meaning, there are other Kholins elsewhere?
Well, not as many as there once were...
So if I'm understanding this correctly, before Gavilar's branch of the Kholin family started their conquest of Alethkar they conquered Kholinar?
Yup. (There's some minor mention of this in Book Three, I believe.)