Vallhunds are more or less Viking corgis - it's the national breed of Sweden, and they look basically like someone crossed a corgi with a wolf. The breed is at least a thousand years old.

Valkyries are impossible to find reference of that isn't more or less softcore porn. There's NO WAY those metal bikini cups are war-safe, folks!

The outfit on the left is based on reference from what I believe is opera costumes.