Henry was born after the death of his father. He fought in the Welsh Campaign in 1294. He was invested as a Knight in 1296. He fought in the Battle of Dunbar on 27 April 1296. He held the office of Warden of Galloway and Ayrshire in September 1296. He held the office of Joint Justiciar of Cumberland, Lancashire and Westmorland in 1297. He held the office of Justiciar of Dumfries in 1297. He held the office of Member of the Council from 1297 to 1298, during King Edward I's absence overseas. He fought in the Battle of Falkirk in 1298. He was created 1st Lord Percy [England by writ] on 6 February 1299. He fought in the Siege of Carlaverock in 1300. He fought in the Siege of Stirling in 1304. He was King's Lieutenant and Captain over all men-at-arms of the West Borders in 1306. He held the office of Constable of Scarborough Castle in March 1308. On 19 November 1309 he bought the territorial barony of Alnwick from Anthony Beck, Bishop of Durham. He was one of the magnates opposed to King Edward II, and took part in the appointment of the Lords Ordainers. He held the office of Joint Keeper of the Marches circa 1311. He held the office of Keeper of the Bishopric of Durham in March 1311. He held the office of Keeper of Bamburgh Castle in December 1311. He held the office of Justice of the Forest Beyond Trent in December 1311.
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