The Family of David Seisyll

by William Addams Reitwiesner

David Seisyll, a Welshman who died ca. 1537 [WG2 Cecil], was the paternal grandfather of William Cecil, 1st Baron Burghley [NCP II:428], lord high treasurer and principal minister to Queen Elizabeth, and ancestor of the Earls of Exeter and the Earls and Marquesses of Salisbury. Selected descendants of David Seisyll include:

David Seisyll m. Alice Dickons [LAPC P58401]
A. Joan Cecil m. Edmund Browne of Stamford. Robert Browne, founder of the Brownists (later called Congregationalists), and recognized by Burghley as a kinsman, is said to have been a descendant of Edmund and Joan.
B.       Richard Cecil m. Jane Heckington [LAPC O29201]
BA.       Elizabeth Cecil m. Sir Robert Wingfield [RPA 769; RMC 895]
BAA.       Dorothy Wingfield m. Adam Claypoole [RPA 213; RMC 214]
BAAA. John Claypoole m. Mary Angell [RPA 214; RMC 214]
BAAAA. James Claypoole, emigrant to Pennsylvania [RPA 214; RMC 215]
BAAAB. Norton Claypoole, emigrant to Delaware [RPA 214; RMC 215]
BAB. Elizabeth Wingfield m. Edward Moryson
BABA. Anne Moryson m. Roger Townsend [Evans 4771]
BAC. John Wingfield m. Elizabeth Gresham [RPA 770; RMC 895]
BACA.       Sir John Wingfield m. Frances Cromwell [RPA 770; RMC 896]
BACAA.       John Wingfield m. Mary Owen [RPA 770; RMC 896]
BACAAA.       Thomas Wingfield, emigrant to Virginia [RPA 770; RMC 896]
BB. Margaret Cecil m. Roger Cave
BBA. Margaret Cave m. Sir William Skipwith [RPA 659; RMC 754]
BBAA. Sir Henry Skipwith 1 Bt m. Amy Kempe [RPA 6599; RMC 754]
BBAAA. Diana Skipwith m. Maj. Edward Dale, emigrants to Virginia [RPA 660; RMC 754]
BBAAB. Sir Grey Skipwith 3 Bt, emigrant to Virginia [RPA 660; RMC 754]
BC. William Cecil (1520-1598), 1st Baron Burghley, Lord Treasurer of England m. Mildred Cooke [LAPC N14601]
BCA. Robert Cecil 1 E Salisbury (1563-1612) [LAPC M7301]

Through David Seisyll's mother, Margred Vaughan f. William, Lord Burghley is related in several ways to his employer, Queen Elizabeth. One of the relationships is:

NN m. Maredudd ab Owain (d. 1265) [WG Rs. ap T. 6] m. NN f. Thomas

Cynan ap Maredudd m. NN
Half Siblings
Owain ap Maredudd m. [two wives]

Gwenllian f. Cynan m. Gruffudd Llwyd ap Rhys
Half 1st Cousins
Llywelyn ab Owain m. [two wives]

Crisli f. Gruffudd Llwyd m. Dafydd Moethe ap Dafydd
Half 2nd Cousins
Thomas ap Llywelyn m. [two wives]

Rhys Moethe m. NN f. Ieuan Fwya
Half 3rd Cousins
Margred f. Thomas m. Tudur ap Gronwy

Rhys Moethe m. [two wives]
Half 4th Cousins
Maredudd ap Tudur m. Margred f. Dafydd Fychan

Hywel Moethe m. [two wives]
Half 5th Cousins
Owain ap Maredudd ap Tudur m. Catherine of Valois

Catrin f. Hywel Moethe m. William Vaughan ap Philip
Half 6th Cousins
Edmund Tudor 1 E Richmond m. Margaret Beaufort

Margred Vaughan f. William m. Richard Seisyll
Half 7th Cousins
Henry VII K of England m. Elizabeth of York

David Seisyll m. Alice Dickens
Half 8th Cousins
Henry VIII K of England m. Anne Boleyn

Richard Cecil m. Anne Heckington
Half 9th Cousins

Half 9th Cousins
Once Removed



Evans -- Richard K. Evans, The ancestry of Diana, Princess of Wales for twelve generations [Boston: NEHGS, 2007].

LAPC -- Gerald Paget, The Lineage and ancestry of H.R.H. Prince Charles, Prince of Wales [Edinburgh & London: Charles Skilton, 1977]

RMC -- Douglas Richardson, Magna Carta Ancestry [Baltimore: Genealogical, 2005].

RPA -- Douglas Richardson, Plantagenet Ancestry [Baltimore: Genealogical, 2004].

William Addams Reitwiesner