The Royces of The Gates of the Moon, the first and greatest of the waycastles which guard the dangerous path up to the Eyrie high above the Vale, are a cadet branch of the Royces of Runestone. They are descended from the First Men who once populated the Vale, although no doubt they have since been heavily intermarried with the Andals who conquered the Vale millenia ago. Lord Nestor Royce has been High Steward of the Vale for the past fifteen years. His son and heir is Ser Albar Royce.
Information about House Royce that reveals spoilers from the books.