Why is the Magna Carta considered the foundation of modern democracy?

The answer

Signed under duress by King John of England in 1215, the Magna Carta established the revolutionary principle that even the king was subject to law, not above it. It guaranteed trial by jury, protection from unlawful imprisonment, and limits on taxation without consent. Though it was annulled within weeks and originally protected only the nobility, its principles were revived in later centuries and directly influenced the U.S. Constitution and the Universal Declaration of Human Rights.