I'm so sorry I'm so late with this review - dd lost it and had to rewrite.
The Sleeping Army
It was certainly a good book and I found no mistakes in the mythology. It was a fun plot and kept the reader constantly hooked. I liked Roskva because she was to the point and took no nonsense from Freya, though was a bit rude and stubborn. Freya was, I'm afraid, a bit annoying. She was silly, patronising and when camping out and offered fish she proved herself picky and irritating.
On the subject of mythology, I think a bit more information would not go amiss, perhaps listing all nine worlds of Yggdrasil (Asgard, Vanaheim, Aflheim, Midgard, Jotunheim, Nidavellir, Muspell, Niflhel, Hel), but perhaps these will come up in a sequel?
To my delight Ratatosk was mentioned, and the nasty bits were not watered down (keeping the nut in Skadi's cleavage, Skadi urinating in the river). I thought the idea of everyone being Norse pagans very interesting and, although some are, it is quite rare nowardays; everyone seems to be more interested in the Egyptian and Greek deities, and while all 3 are very good, they are also very different, so it is nice to see the Norse get more attention.
All in all, it was a good read and I enjoyed it; well-written, with well realised characters.
All errors will be down to my inability to read dd's writing properly, btw! - Jux