Over the course of the 12th century, it became customary that general taxation should not be introduced and collected without the agreement of the barons
In the medieval period, English society was organised according to the feudal system, a system of loyalty where each rank in society supported the rank above them and were supported by the ranks below them
The Barons held power as a result of their ties with the king through land ownership and had an obligatory right to give counsel to the king, which he was required to follow
During the Great Council meeting, the King agreed to the Provisions of Oxford, stating that a council of 15 barons would be in charge of the Great Council, elected by 24 men - 12 by the king and 12 by the barons
Agreeing to the Provisions of Oxford meant the King also agreed that foreign members of the royal household would be banished and castles would be held by Englishmen