A terrible world of fire and ice. Situated close to the eye of terror, Fenris takes an eliptical orbit around it's sun, resulting in the extremes of weather patterns. As it approaches the closest point to the sun, the land-mass suffers from the gravitational forces. The only stable continent is the polar land mass of Asaheim.
The population live in a feudal and tribal warrior culture, from whom the Spacewolves recruit exclusively. Their fortress, the Fang, is buried deep within the stable polar continent of Asaheim, and is considered one of the greatest citadels in the imperium.
(Ref: Codex Spacewolves, 2nd ed;)