No one would mistake King John and the barons of England for democrats, but the document they signed on the field of Runnymeade in 1215 is a landmark in the development of constitutional government.
The barons had become outraged at what they viewed as the king's abuse of traditional feudal law, which had given them considerable autonomy in their dealings with the monarch. When King John refused their demands, they raised an army and forced him to sign the Magna Carta (Great Charter), which contains 63 articles, most of them a list of rights that chiefly benefited the land-owning nobility and the church.
Nevertheless, a number of the provisions were later applied to all the people of England; others became the foundation for the country's legal system. The Magna Carta states, for example, that the king must seek the advice and consent of the barons in all important matters of state, including the raising of taxes. In later centuries, these provisions were used to assert that no law could be passed or tax raised without the consent of the body representing all the people, the Parliament. (In the American Revolution, colonists seeking independence turned this idea against England with the cry of "no taxation without representation.") The guarantee of due process of law and trial by jury of one's peers can also be traced to provisions in the Magna Carta.
This evolution of the Magna Carta's feudal rights into constitutional rights of ordinary people took centuries, since many later English kings successfully ignored the charter. Only in the wake of the Glorious Revolution of 1688 did England succeed in establishing a durable constitutional monarchy with Parliament as the nation's supreme law-making body. The task of reforming Parliament itself into a broadly representative, democratic institution would take more than another century.