In the base game (without DLCs):
- There are nine holds in Skyrim.
- There are nine Dragon Priests.
- There are nine Divines (if you count Talos).
- There are nine Shadowmarks.
- There are nine types of Dragons.
- There are nine named Dragons.
- Nine is a multiple of three, which is the number of words in a Dragon Shout.
- Eighteen, the number of skills in the game, is a multiple of nine.
- 1,320,969,600 is Unix Time for 00:00 on 11/11/2011, the release date for Skyrim. This is evenly divisible by nine.
Okay, maybe that last three on that list begins to stretch things a bit, but I think the first portion (and probably some others I've not yet realized - if anyone else thinks of any, feel free to edit them into here) are good demonstrations that the number nine seems to have some particular importance in Skyrim's design and culture. Is there any explanation for this, either in-game or from Bethesda? Can it be tied to the Norse culture from which much of Skyrim's seems to be derived?
To be clear, I'm not asking for any sort of speculation here. I figure the answer either lies in some knowledge of Tamrielic or (real-world) Norse mythology with which I am unfamiliar, or it may have been something already addressed by Bethesda separately. Any answer that cannot provide a solid reference to one of those, in support itself, would be off-topic.