Warden of the White Knife
The castle of the Wolf's Den was raised by King Jon Stark to guard the mouth of the White Knife at the Bite. After being expelled from the Reach, the Manderlys received the Wolf's Den from House Stark in return for loyally defending the river for their new liege lords in Winterfell. The Manderlys then developed the city of White Harbor and fortified the White Knife's defenses.
A Dance with Dragons