Editing 1231 (section)

==== Britain ====
* Spring &ndash; [[Hubert de Burgh, 1st Earl of Kent|Hubert de Burgh]] becomes a powerful lord in the [[Welsh Marches]], controlling the castles at [[Cardigan Castle|Cardigan]] and [[Carmarthen Castle|Carmarthen]]. He begins to threaten the local Welsh leaders, [[Llywelyn the Great]] launches a campaign against Norman lordship in [[Wales]].
* [[August 13]] &ndash; King [[Henry III of England|Henry III]] orders the sheriffs of [[Hampshire]], [[Dorset]]shire and [[Wiltshire]] to give [[Simon de Montfort, 6th Earl of Leicester|Simon de Montfort]] the possession of the lands of his father, [[Simon de Montfort, 5th Earl of Leicester|Simon de Montfort the elder]].
* December &ndash; Henry III ends his Welsh campaign and makes peace with Llywelyn the Great.<ref>Hywel Williams (2005). ''Cassell's Chronology of World History'', p. 138. {{ISBN|0-304-35730-8}}.</ref>
* The [[University of Cambridge]] is recognised by a writ of authority over its townspeople from Henry III.<ref>[[Close Roll]]s.</ref>