Refusal by one party to obey this law led to an uprising supported by Louis VIII and led by Robert Fitzwalter; that ruler had previously lost control of Brittany when Philip Augustus was victorious at the Battle of Bouvines. This (*) document's Clause 61 gave a certain group of barons the power to override unlawful acts of the king. For 10 points, name this charter signed 
Refusal by one party to obey this law led to an uprising supported by Louis VIII and led by Robert Fitzwalter; that ruler had previously lost control of Brittany when Philip Augustus was victorious at the Battle of Bouvines. This (*) document's Clause 61 gave a certain group of barons the power to override unlawful acts of the king. For 10 points, name this charter signed at Runnymede by King John in 1215.
Refusal by one party to obey this law led to an uprising supported by Louis VIII and led by Robert Fitzwalter; that ruler had previously lost control of Brittany when Philip Augustus was victorious at the Battle of Bouvines.
Magna Carta