Elizabeth de Mortimer was born February 1371 in Usk, Monmouthshire, Wales, United Kingdom to Edmund Mortimer, 3rd Earl of March (c1352-1381) and Philippa Plantagenet, 5th Countess of Ulster (1355-1382) and died 20 April 1417 of unspecified causes. She married Henry Percy (1364-1403) 10 December 1379 JL . She married Thomas de Camoys, 1st Baron Camoys (c1351-1421) 3 June 1406 JL . Alfred the Great (849-899)/s, Charlemagne (747-814)/s, Henry II of England (1133-1189)/s, Hugh Capet (c940-996)/s, William I of England (1027-1087)/s.
|Offspring of Elizabeth de Mortimer and Henry Percy (1364-1403)|
|Henry Percy, 2nd Earl of Northumberland (c1392-1455)||3 February 1392||22 May 1455||Eleanor Neville (1398-1472)|
|Elizabeth Percy (1393-1437)||1395||26 October 1436||John Clifford, 7th Baron de Clifford (1388-1421) John Clifford, 7th Baron de Clifford (1388-1421) Ralph Neville, 2nd Earl of Westmorland (1406-1484)|
|Offspring of Elizabeth de Mortimer and Thomas de Camoys, 1st Baron Camoys (c1351-1421)|
|Roger de Camoys (c1406-1473)|
|Alice de Camoys (1407-1455)||1407 Usk, Monmouthshire, England, United Kingdom||1455||Leonard Hastings (1396-1455)|