House Flint of Widow's Watch is a noble house of the North, seated at the salt-bitten castle that gives them their name on the easternmost cape of the kingdom. They are reckoned the most powerful of the three Flint branches, though the mountain Flints will tell anyone who listens that theirs is the older line and that the Widow's Watch and Flint's Finger houses are the issue of younger sons who came down out of the high country looking for land and wives. A semi-canon blazon gives their arms as a blue field strewn with whitecaps, surmounted by a yellow chief with a crested line bearing a pair of blue eyes, and their words as "Ever Vigilant," fitting for a house posted to watch the Shivering Sea for sails coming out of the east.
The Flints are old enough that legend whispers the Night's King himself may have been one of them, and the dark name of Lord Commander Rodrik Flint, who tried to make himself King-Beyond-the-Wall, still clings to the line. The Nightfort remembers brave young Danny Flint, raped and murdered there in girl's clothing. In happier centuries a branch of House Flint held the Wolf's Den for a hundred years after the extinction of the Greystarks, an inheritance later given over to the Manderlys when they were granted White Harbor.
By the time of A Game of Thrones the seat is held by Lady Lyessa Flint, Lady of Widow's Watch. Her grown son Robin Flint rides south with Robb Stark as one of the thirty highborn youths sworn to the Young Wolf's person, an older head in a young man's guard, and falls at the Red Wedding ringed by Freys with their daggers rising and falling. Lady Lyessa herself excuses the house from the harvest feast at Winterfell, being heavy with child and with sickness loose in her halls, and when the war turns and the Boltons claim the North her ships note the passage of Salladhor Saan's fleet along the eastern coast. Lord Wyman Manderly counts the Flints of Widow's Watch among the houses that will follow his lead should he declare for Stannis Baratheon, a measure of how much weight the family carries among the eastern lords.