William The Brown (3rd Earl of Ulster) De Burgh
1312 - 1333 (21 years)(
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- 1 William The Brown (3rd Earl of Ulster) De Burgh [1] b. 1312 d. 6 Jun 1333
- Maud Plantagenet b. Abt 1310 d. 1377
- 2 Elizabeth (Countess of Ulster) De Burgh [1.1] b. 6 Jul 1332 d. 10 Dec 1363
- Lionel of Antwerp (Duke of Clarence) Plantagenet b. 29 Nov 1338 d. 1368
- 3 Phillippa (Countess of Ulster) Plantagenet [1.1.1] b. 16 Aug 1355 d. 5 Jan 1377-1378
- Edmund (3rd Earl of March) De Mortimer b. 1351 d. 27 Dec 1381
- 4 Roger (4th Earl of March) Mortimer [1.1.1.1] b. 1 Sep 1373 d. 20 Jul 1398
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- 4 Elizabeth (of March) Mortimer [1.1.1.2] b. 12 Feb 1370-1371 d. 20 Apr 1417
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- 4 Philippa (of March) Mortimer [1.1.1.3] b. 21 Nov 1375 d. 1401
- 4 Edmund (Sir) Mortimer [1.1.1.4] b. 9 Nov 1376 d. 1409
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- 4 John (Sir) Mortimer [1.1.1.5] d. Yes, date unknown
- 4 Roger (4th Earl of March) Mortimer [1.1.1.1]
- 3 Phillippa (Countess of Ulster) Plantagenet [1.1.1]
- 2 Elizabeth (Countess of Ulster) De Burgh [1.1]