However, the Norman Conquest did not affect English as much as the Angles and the Saxons' vitory about 600 years earlier, which led to Old English replacing Celtic.
In the ninth and 10th centuries, the castles being constructed across Christian Europe were generally wooden structures built on top of artificial mounds that, after the Norman conquest, were called mottes.
And if the monarchy is an overthrown Game of Throne style by 2066 that will mark the 1000 year anniversary of the Norman conquest and the near-continuous reign of William's descendants.