This is about the grandfather of Duke Borric not his and not the son of Arutha
Nicholas conDoin was the third and youngest son of the King of the Kingdom of the Isles.
During the war of Great Kesh and the Keshian Confederacy, Nicholas brought the Kingdom armies westward to Bosania, a Keshian province and laid waste to Walinor and siege to Natal. He was stopped only ten miles north of Bordon and could not conquer the cities called Free Cities. He thus established the Western Realm and the Kingdom of the Isles expanded into the Western Lands around the Bitter Sea across the Grey Towers Endless Sea.
His son had been good neighbors to the Free Cities, treating fairly and generously with them, as did his grandson Duke Borric conDoin.