- "It wasn't for murder the gods cursed the Rat Cook, or for serving the King's son in a pie... he killed a guest beneath his roof... that's something the gods can't forgive."
- ―Bran Stark
The rat cook is the subject of legends and myths in the Seven Kingdoms.
According to these legends, a king once paid a visit to the Nightfort, then the chief castle on the Wall. For unknown reason (Bran Stark cannot remember the exact reason when he recounts the tale), the cook killed the king's son and served his flesh in a pie to the unknowing king. The king enjoyed the pie so much he asked for a second helping.
The gods cursed the cook by turning him into a fat, white rat which could only survive by feasting on its young. He was condemned to run the halls of the Nightfort. The gods were not offended by the murder, nor even by cooking the son and cannibalistically feeding him to his own father (for a man has a right to vengeance). What the gods could not forgive and cursed the cook for was that he broke the laws of hospitality and protection, which are held to be sacred above all others.
In the books
The story is much the same in the A Song of Ice and Fire novels, except that the king in the story is identified as an Andal ruler, not the King in the North. It is extremely well-known in the North and there is even a popular song about it.
- The Rat Cook at A Wiki of Ice and Fire (spoilers from the books)