King-Beyond-the-Wall

The King-beyond-the-Wall is a title given to a wildling chief or leader who manages to unite a significant number of the northern tribes under his command, enough to pose a threat to the Seven Kingdoms. Uniting the fractious and independently-minded tribes (who often have radically different traditions, customs and laws) into a single force is extremely difficult, only possible with a leader of impressive military skill and personal charisma. Most of the time, the wildlings are not so united.

At the present time, the wildlings are united under the command of Mance Rayder, the current King-beyond-the-Wall.

Season 1
Ser Alliser Thorne names Mance Rayder as the commander of the wildlings beyond the Wall and indicates he has held this post for more than ten years.

When Osha, Stiv and Wallen - deserters from Rayder's army - inadvertantly imprison Bran Stark, they debate taking him back to Mance Rayder to win forgiveness. They reject the notion, which is rendered moot when Robb Stark and Theon Greyjoy arrive. Osha later tells Maester Luwin that they were fleeing the awakening of an old, remorseless foe, the White Walkers, indicating that the wildlings are already aware of the threat of the Walkers and may already be fighting them.

Lord Commander Jeor Mormont, puzzled by reports of Mance Rayder's forces gathering in the mountains, decides to lead a reconnaisance-in-force to determine Rayder's intentions and level of threat.

In the books
In the Song of Ice and Fire novels, Mance Rayder is a former member of the Night's Watch who turned his cloak and fled beyond the Wall many years before the beginning of the series. As an outsider, his uniting of the wildling tribes is even more impressive.

Previous Kings-beyond-the-Wall included Raymun Redbeard, who invaded the North some 120 years ago and was stopped by Lord Willam Stark (at the cost of his life) and the Umbers. The most storied King was Joramun, who is said to have lived thousands upon thouands of years ago. According to legend he awoke giants from the earth using a magical horn and made common cause with the Night's Watch in its infancy to destroy the Night's King, a formidable and evil sorcerer.