Overview
Isabelle of Blois or Elizabeth of Blois (died 1248 or 1249) was the lady of Amboise by marriage and from 1218 until her death the countess of Chartres in her own right. She founded three Cistercian houses for nuns. Twice widowed, she was succeeded by her daughter, Matilda.
Family
Isabelle (Elizabeth) was born probably before 1180. She belonged to the highest nobility of France. She was the younger daughter of Count Theobald V of Blois and Chartres and Alice, daughter of King Louis VII and the Duchess Eleanor of Aquitaine. She had a brother, Count Louis I of Blois; an older sister, Margaret; and another sister, Alice, who was the abbess of Fontevraud between 1209 and 1218.
Isabelle was married twice. In 1190, she was married to . They had six children: Hugh, Matilda, John, William, Alice and Dionysia. Sometime before 1209, Sulpice and Isabelle jointly founded the Cistercian . When Sulpice died, sometime between 1214 and 1218, Hugh inherited Amboise. He in turn was succeeded by Matilda around 1237. The fates of the four younger children of Isabelle and Sulpice are unknown. Isabelle made several gifts to Moncé for the benefit of Sulpice's soul, including endowing a priest there to say mass daily. In 1218, she married , lord of Montmirail and Oisy. No children of her second marriage are known.
Countess
When Isabelle's nephew, Count Theobald VI, died without heirs in 1218, his counties were divided between his aunts. The initiative to divide them came from King Philip II. Margaret received Blois and Isabelle received Chartres. Her husband, John, paid a feudal relief to the king, who in August confirmed Isabelle's succession to the county and to some associated castellanies with her cousin, Count William II of Perche, standing as surety. In July 1221, William gave Montigny-le-Chartif to his cousin and her heirs.
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