Henry was born 25 March 1273, in England, seven months after the death of his father, Henry Percy. [2] His two brothers, William and John, died without heirs. [3]
Memorials of the abbey of St. Mary of Fountains (page 148):
"Immediately in front of the high altar was interred, in 1315, Lord Henry Percy of Alnwick, whose valorous feats against the Scots during the wars of King Edward I.,...you will find amply detailed in the Baronage of Dugdale; but the most diligent search I could institute discovered neither an indication of his monument nor of his tomb."
Kings in the North - the House of Percy in British History by Alexander Rose 2002
Medieval Lands, database online, author Charles Cawley, (Foundation for Medieval Genealogy, 2006-2013), England, Earls created 1138-1143, Chapter 8, B. EARLS of NORTHUMBERLAND 1377-1527 (PERCY) 6.c. Henry de Percy
Collins, Arthur, and Egerton Brydges. Percy, Duke of Northumberland, Collins's Peerage of England Genealogical, Biographical, and Historical. Vol. II. London: Printed for F.C. and J. Rivington, Otridge and Son ... [et Al., 1812. 217-366. Print.