Oxford Parliament (1258)

The Oxford Parliament (1258), also known as the "Mad Parliament" and the "First English Parliament", assembled during the reign of Henry III of England. It was established by Simon de Montfort, 6th Earl of Leicester. The parlour or prolocutor (Speaker) was Peter de Montfort under the direction of Simon de Montfort. Simon de Montfort led the Parliament and the entire country of England for 18 months, from 1264 until his death at the Battle of Evesham.

King Henry III of England had agreed with Pope Innocent IV that his (Henry's) son Edward should become King of Sicily following the death of Frederick II, Holy Roman Emperor. The Pope offered to partly fund the efforts to overthrow the Holy Roman Empire forces still in Sicily, but following Innocent's death and the succession of Pope Alexander IV, issues began to arise. Alexander did not want to fund the ongoing efforts, and should Henry not complete his task then he would be excommunicated. As a result, the King sought further taxation to repay his efforts from Parliament, existing Royal funds failing to cover debts owed, even after selling Edward's lands to William de Valence.

In the parliament in London on 2 April 1258, the great magnates' disaffection with the King reached breaking point. An agreement was made to look at the issues of supply on behalf of the King, to which Henry and Edward agreed on 2 May. At the Oxford Parliament on 11 June, led by Simon de Montfort, Henry accepted a new form of government, laid out in the Provisions of Oxford, in which power was placed in the hands of a privy council, a council of fifteen members who were to supervise ministerial appointments, local administration and the custody of royal castles. Parliament, meanwhile, which was to meet three times a year, would monitor the performance of this council.

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