Henry Percy, 3rd Baron Percy

Henry Percy, 3rd Baron Percy of Alnwick, was born around 1321 as the eldest son of Henry de Percy, 2nd Baron Percy, and Idoine de Clifford. He began his military career serving in France under the Earl of Arundel in March 1344. By August 1346, he participated in the Battle of Crécy and later served in Gascony under the Earl of Lancaster.

In July 1352, Henry Percy was appointed joint warden of the marches towards Scotland and became the keeper of Roxburgh Castle and sheriff of Northumberland in September 1355. He took part in the invasion of Scotland in 1356 and was involved in the negotiations for the treaty of Berwick in October 1357. He continued his military service in France, acting as marshal of the royal army at Calais in September 1355 and joining Edward III's campaign to capture Rheims in 1360.

Henry Percy died on or about 18 May 1368, likely at Alnwick Castle, and was buried in Alnwick Abbey. He was succeeded by his eldest son, who became Henry Percy, 1st Earl of Northumberland.