William the Conqueror was one of the most powerful and influential of all the kings of England. A battle-hardened veteran, he used his military experience to defeat the Saxon king Harold at Hastings, then to impose his iron control on the newly conquered realm. He brought with him from Normandy a new ruling dynasty, a new aristocracy and a new church leadership. He oversaw the most complete change of land-holding ever witnessed in England as evidenced by Domesday Book. He introduced the castle and a new form of church architecture to England as well as a much strengthened military feudal system. His conquest also brought fundamental changes to the English language, literature and law. Above all, he created a model of kingship that was admired and imitated for centuries afterwards and shaped an axis of Western European power which survives to this day.