Henry was only 9 years old when he came to the throne, which he occupied for 56 years. While he was a minor the land was ruled by the Earl of Pembroke and Hubert de Burgh. His personal rule was weak and ineffective. Many followers from his wife's country were given important positions and the English barons became restless. By 1258 Henry was compelled to hand power to these barons, led by Simon de Monfort. War broke out between the barons and Henry, and he was defeated and made prisoner at Lewes. He had to agree that a new Great Council or Parliament, as it was now called for the first time, be set up. The members of this parliament would be chosen half by the King and half by the barons. In 1265 his son Edward defeated the barons at Evesham and de Monfort was killed. After this, although Henry remained King, the real ruler was Edward. Henry's most lasting contribution to his country was his advancement of the design of Gothic architecture. In particular he instituted the building of a new Abbey at Westminster and in Oct 1269 the relics of the Saint, Edward the Confessor, were laid in a shrine behind its altar.
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