Edmund Mortimer, 3rd Earl of March, Earl of Ulster, was born circa 1352 in Llyswen, Brecknockshire, Wales, United Kingdom to Roger Mortimer, 2nd Earl of March (1328-1360) and Philippa de Montacute (1332-1382) and died 27 December 1381 Cork, Ireland of unspecified causes. He married Philippa Plantagenet, 5th Countess of Ulster (1355-1382) 1368 JL . Hugh Capet (c940-996)/s.
|Offspring of Edmund Mortimer, 3rd Earl of March and Philippa Plantagenet, 5th Countess of Ulster (1355-1382)|
|Elizabeth Mortimer (1371-1417)||February 1371 Usk, Monmouthshire, Wales, United Kingdom||20 April 1417||Henry Percy (c1363-1403) Henry Percy (c1363-1403) Thomas de Camoys, 1st Baron Camoys (c1351-1421)|
|Roger Mortimer, 4th Earl of March (1374-1398)||11 April 1374 Usk, Monmouthshire, Wales, United Kingdom||20 July 1398 Kells, County Meath, Ireland||Alianore Holland (c1373-1405)|
|Philippa Mortimer (1375-1400)||21 November 1375 Ludlow Castle, Ludlow, Shropshire, England, United Kingdom||26 September 1400 Halnaker, Sussex, England, United Kingdom||John Hastings, 3rd Earl of Pembroke (1372-1389) Richard FitzAlan, 11th Earl of Arundel (1346-1397) John Hastings, 3rd Earl of Pembroke (1372-1389) Richard FitzAlan, 11th Earl of Arundel (1346-1397) Thomas Poynings, 5th Baron St John (-1429)|
|Edmund Mortimer (1376-1409)|