Historical destiny of England after the reign of William the Conqueror permanently intertwined with the fate of France. William continued to be the ruler of Normandy region in northern France , and his great-grandson of Henry II Plantagenet , King of England (1153-1189 years), owned almost half of French land (albeit on terms vassal possession : his overlord was considered the king of France ) . Henry made several important reforms . Among them, reforming the judicial process by involving adjudication besides judges " decent people " among the subjects , it is here and subsequently developed a jury trial.