Castles. The Normans were master castle builders. After 1066, England witnessed a massive castle building programme on the orders of William the Conqueror. First, motte and bailey castles were built.Once William had firmly established his rule in England, he built huge stone keep castles.By the time of Edward I, concentric castles were being built.fter 1066, England witnessed a massive castle building programme on the orders of William the Conqueror. First, motte and bailey castles were built.