William, Earl of Pembroke 4 Marshal {M} [P107] = Isabel, Countess Strigoil de Clare {F} [P64]

Married August 1189, London
Isabel, Countess Strigoil de Clare:

Alias Isabel, Countess Strigoil Marshal (August 1189)
Born 1174
Died 1220, Tintern Abbey
Also Known as Countess of Pembroke

William, Earl of Pembroke 5 Marshal {M} [P109]

Born 1190

Richard, Earl of Pembroke 6 Marshal {M} [P110]

Born 1191

Walter, Earl of Pembroke 8 Marshal {M} [P112]

Born 1199

Isabella, Lady Marshal {F} [P98] = Gilbert de Clare¹ {M} [P72] > Family [F26]

Married Monday 9 October 1217, Tewkesbury Abbey
Isabella, Lady Marshal:

Alias de Clare
Alias Isabella, Lady Cornwall
Born Monday 9 October 1200, Pembroke Castle, Wales
Died Tuesday 17 January 1240, Berkhamsted Castle, Herts
Buried Beaulieu Abbey, Hampshire
Some say Isabella died on the 15th Jan. She died in childbirth.

Gilbert de Clare:

Born 1180
Died Friday 25 October 1230, Penros, Brittany
Buried Tewkesbury
7th Earl of Clare, 6th Earl of Hertford and 5th Earl of Gloucester.

Some sources say married Isabella 1214

Chronology

1215 among twenty five barons appointed to carry out Magna Carta
1216 excommunicated by Innocent III
1217 succeeded his father in the earldom of Hertford
1217 inherited, through his mother, the earldom of Gloucester
1228 fought against the Welsh
1230 attended Henry III to Brittany

= Richard, Earl of Cornwall {M} [P203] > Family [F71]

Married Sunday 30 March 1231, Fawley Church, Bucks.

Maud Marshal {F} [P108]

Gilbert, Earl of Pembroke 7 Marshal {M} [P111]

Anselm, Earl of Pembroke 9 Marshal {M} [P113]

Sibyl Marshal {F} [P115]

Eva Marshal {F} [P116]

Joan Marshal {F} [P117]

1 : "The Complete Peerage"; Page Vol v. pp 694-6; Secondary evidence
1a: "The Dictionary of National Biography Volume VI"; Page 378; Secondary evidence