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 .
Children
| Name | Birth | Death | Joined with |
| 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) Ralph Neville, 2nd Earl of Westmorland (1406-1484) |
| Name | Birth | Death | Joined with |
| Roger de Camoys (c1406-1473) | |||
| Alice de Camoys (1407-1455) | 1407 Usk, Monmouthshire, England, United Kingdom | 1455 | Leonard Hastings (1396-1455) |
Footnotes (including sources)
| ‡ General |
| Ω Birth |
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