Joan de Munchensi

Joan de Munchensi or Munchensy (or Joanna), Lady of Swanscombe and Countess of Pembroke (c. 1230 – aft. September 20, 1307), was the daughter of Joan Marshal and granddaughter of William Marshal, 1st Earl of Pembroke and Isabel de Clare, 4th Countess of Pembroke suo jure.

William Marshal was the great Lord Marshal who served five successive Kings of England and died in 1219. William's five sons each in turn became Earl of Pembroke, but all died childless. His inheritance was thus divided among his daughters. Joan Marshal, the fourth daughter, married Warin de Munchensi (or Munchensy), Lord of Swanscombe. They were survived by one daughter, Joan de Munchensi, who (owing to Joan Marshal's death soon after her daughter's birth) was brought up by her stepmother, Warin's second wife, Dionisie de Munchensi.

In 1247 three sons of Hugh X of Lusignan, in difficulties after the French annexation of their territories, accepted Henry III's invitation to come to England. The three were William of Valence, Guy of Lusignan and Aymer. The king found important positions for all of them and William was soon married to Joan. Her portion of the Marshal estates included the castle and lordship of Pembroke and the lordship of Wexford in Ireland. The custody of Joan's property was entrusted to her husband. She also, apparently, transmitted to him the title of Earl of Pembroke; he thus became the first of the de Valence holders of the earldom.

William of Valence died in 1296. Accounts of the offspring of William and Joan vary, but all say that there were five children, others seven including the last two:

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