Barrow King

"In those days, the Starks were not the greatest house in the North, and Winterfell was not the greatest castle. Barrowton was the oldest, dating to the First King, and the Starks fought the Barrow Kings for a thousand years"

- Roose Bolton

Barrow King was a title held be the ruler of the Barrowlands. It was discontinued after House Stark conquered the North following a the Thousand Years War.

In the books
In the A Song of Ice and Fire novels, the Barrow Kings were a dynasty of kings who ruled the Barrowlands. They claimed descent from the First King and monarchy over all First Men. Some of them allied with the Marsh Kings to defeat southron invader who attempted to pass the Neck.

It is claimed by singers that the Barrow Kings fought against the Kings of Winter north of the Barrowlands in the Thousand Years War. However, runes of the First Men claim that the conflict only lasted around two hundred years. The conflict ended when the last Barrow King surrendered to Winterfell, with the Stark King receiving his daughter in marriage.

House Dustin of Barrowton claim descent from the First King and the Barrow Kings.

Maester Kennet's Passages of the Dead makes mention of a curse that was supposedly placed on the Great Barrow, weakening and making corpselike any living man who dared to equal the First King. Some maesters believe that the Night's Queen may have actually been a daughter of a Barrow King, as they were often connected with graves.