(Asked after reading this answer in SciFi&Fantasy SE):
I think that whole Stark (York) and Lanister (Lancaster) feud is reference to War of Roses. Both houses descended from house Plantagenet whose sigil was three lions on red background, while Edvard IV , first Yorkist king of England had 2 white wolves on his coat of arms. http://en.wikipedia.org/wiki/File:Coat_of_Arms_of_Edward_IV_of_England_%281461-1483%29.svg
At least, i think those are wolves :)

Is there some historical/heraldic source confirming just what the animals on Edward IV's Coat of Arms were?