The Magna Carta, signed in 1215 by King John of England, is a landmark document in the development of constitutional government. It established the principle that everyone, including the monarch, is subject to the law, and guaranteed certain rights to individuals, including due process and protection from unlawful imprisonment. The Magna Carta laid the groundwork for the emergence of parliamentary democracy and influenced many constitutional documents worldwide, including the U.S. Constitution and the Universal Declaration of Human Rights. It signified a crucial shift towards recognizing individual liberties and limiting the power of the monarchy.