When Saxon England was conquered by Duke William of
Normandy in 1066, the new king took more power than
any English ruler had ever enjoyed - confiscating the
estates of the Saxon Earls and distributing them amongst
his own followers. At the same time, he took measures to
control the church, and appointed travelling Royal judges
whose decisions gradually evolved into today's Common
Law.
Although he was all-powerful, King William also sought advice, and regularly summoned councils of his chief subjects:
archbishops and bishops, abbots, earls, barons, and the King's own ministers. The king was not obliged to take the council's advice, but their information and opinions became invaluable in law-making and administration. They were, in effect, an early form of what was later to become the British Parliamentary system.