June 15 - 1215 - King John Seals the Magna Carta
Almost all of the Barons of England hated King John, and with good reason. John had been fighting in France, only succeeding in losing most of his continental holdings and spending money at a remarkable rate. To pay for this, he asked his barons for more money in increasingly unspecified ways. So the Barons rose up and took over London, then forced King John to affix his seal to a document known as Magna Carta Libertatum (The Great Charter of Liberties.) Guaranteeing a process for taxation, the raising of armies, and redress of grievances, Magna Carta also provided for a council of 25 barons to oversee the King. King John basically ignored it and a civil war, the First Barons' War, broke out between John and his barons. Within a year, John would die of dysentery while campaigning. His nine year old son, Henry III, became King, and his regent William Marshal helped swing barons back to the Royalist side by agreeing to enforce Magna Carta. Since that point, Magna Carta has been one of the foundational documents in the British Constitutional tradition, checking the power of the monarch.