The Privy Council is the British Crown's private council. It is composed of more than three hundred members, including cabinet members, distinguished scholars, judges, and legislators. Once a powerful body, it has lost most of the judicial and political functions it exercised since the middle of the seventeenth century and has largely been replaced by the Cabinet.
The Privy Council derived from the King's Council, which was created during the Middle Ages. In 1540 the Privy Council came into being as a small executive committee that advised the king and administered the government. It advised the sovereign on affairs of state and the exercise of the royal prerogative. It implemented its power through royal proclamations, orders, instructions, and informal letters, and also by giving directions to and receiving reports from the judges who traveled the circuits, hearing cases in cities and towns, twice a year. It concerned itself with public order and security, the economy, public works, public authorities and corporations, local government, Ireland, the Channel Islands, the colonies, and foreign affairs.
The inner circle of advisers in the Privy Council met in the royal chamber or cabinet and was therefore called the cabinet council. In the eighteenth century, the cabinet became the council for the prime minister, the leader of Parliament. The United States adopted the cabinet idea, though its legal status is not identified in the Constitution. Cabinet members are presidential advisers who serve as executive branch department heads.
The power of the Privy Council disappeared between 1645 and 1660 during the English Civil War and the government of Oliver Cromwell. It never recovered its former position. Long policy debates shifted to Parliament, and important executive decisions went to committees. In modern days members of the Privy Council rarely meet as a group, delegating their work to committees.