From 1242 to 1243 Alan did military service in Gascony. He held the office of Justice of Chester and the four cantrefs of North Wales in 1250. He was Deputy under Prince Edward from February 1254 to 1255. He held the office of Justiciar of Ireland from 1256 to 1258. He held the office of Constable of Northampton Castle between 1261 and 1263. He held the office of Sheriff of Northamptonshire between 1261 and 1264. He held the office of Constable of Rockingham Castle between 1261 and 1264. He held the office of Justice of the Forests south of Trent between 1261 and 1264. He held the office of Constable of the Tower of London from 1267 to 1268. He held the office of Constable of Northampton Castle between February 1267 and June 1267. He died on 10 August 1270, from injuries inflicted by the 7th Earl of Surrey.
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