The Parliament of England was the legislature of the Kingdom of England, existing from the early 13th century until 1707, when it became the Parliament of Great Britain after the political union of England and Scotland created the Kingdom of Great Britain.
In 1066, William of Normandy introduced what, in later centuries, became referred to as a feudal system, by which he sought the advice of a council of tenants-in-chief (a person who held land) and ecclesiastics before making laws. In 1215, the tenants-in-chief secured Magna Carta from King John, which established that the king may not levy or collect any taxes (except the feudal taxes to which they were hitherto accustomed), save with the consent of his royal council, which gradually developed into a parliament.
Over the centuries, the English Parliament progressively limited the power of the English monarchy which arguably culminated in the English Civil War and the trial and execution of Charles I in 1649. After the restoration of the monarchy under Charles II, and the subsequent Glorious Revolution of 1688, the supremacy of Parliament was a settled principle and all future English and later British sovereigns were restricted to the role of constitutional monarchs with limited executive authority. The Act of Union 1707 merged the English Parliament with the Parliament of Scotland to form the Parliament of Great Britain. When the Parliament of Ireland was abolished in 1801, its former members were merged into what was now called the Parliament of the United Kingdom.
Under a monarchical system of government, monarchs usually must consult and seek a measure of acceptance for their policies if they are to enjoy the broad cooperation of their subjects. Early kings of England had no standing army or police, and so depended on the support of powerful subjects. The monarchy had agents in every part of the country. However, under the feudal system that evolved in England following the Norman Conquest of 1066, the laws of the Crown could not have been upheld without the support of the nobility and the clergy. The former had economic and military power bases of their own through major ownership of land and the feudal obligations of their tenants (some of whom held lands on condition of military service). The Church was virtually a law unto itself in this period as it had its own system of religious law courts.
In order to seek consultation and consent from the nobility and the senior clergy on major decisions, post-Norman Conquest English monarchs called Great Councils. A typical Great Council would consist of archbishops, bishops, abbots, barons and earls, the pillars of the feudal system. When this system of consultation and consent broke down, it often became impossible for government to function effectively. The most prominent instances of this prior to the reign of Henry III are the disagreements between Thomas Becket and Henry II and between King John and the barons. Becket, who served as Archbishop of Canterbury between 1162 and 1170, was murdered following a long running dispute with Henry II over the jurisdiction of the Church. John, who was king from 1199 to 1216, aroused such hostility from many leading noblemen that they forced him to agree to Magna Carta in 1215. John's refusal to adhere to this charter led to civil war (see First Barons' War).