How did the Magna Carta limit King John’s power?

The Magna Carta limited King John’s power by establishing that the sovereign was subject to the rule of law rather than standing above it. Drafted at Runnymede in 1215, the charter sought to curb the king’s arbitrary exercise of authority, which had been characterized by excessive taxation and the abuse of feudal rights.123

Key limitations included:

• Legal Accountability: It mandated that the king adhere to established law and custom, protecting "free men" from arbitrary actions. Clause 39 famously promised judgment by peers or by the law of the land.12
• Financial Constraints: It set specific limits on reliefs (inheritance duties), preventing the king from imposing excessive financial burdens on his barons.2
• Enforcement Mechanisms: Clause 61 authorized a council of 25 barons to act as a security measure, effectively granting subjects the right to challenge the king if he violated the charter’s terms.3

While the 1215 document failed to prevent immediate civil war, it fundamentally shifted the concept of kingship by formalizing the principle that a monarch’s power is defined and restricted by legal contract.23