Olivier III de Clisson (1280–1320), was a Breton Marche Lord and knight.de Corsin, G. Grand Lords of Haute-BretagneKerherve, J., The nobles of Brittany from the middle ages to the present day, Rennes 1999.
Lord of Southern Brittany Olivier III continued expanding the de Clisson influence outside Brittany and in 1299, married Isabeau de Craon (1278 - July 30, 1350), daughter of Maurice VI de Craon. The Lords of Craon were mainly Norman with a history as former adversaries of the Dukes of Brittany.Bougraud, F. Some notes on the Lords of Clisson (1180-1320) in the Bulletin of the Archaeological and Historical Society of Nantes and Loire Atlantique, ed. 135, 2000, Pgs. 112-115Prosper, L. Breton Biography, collection of notices on all Bretons, 1852-1857, pg 358, Infobretagne.com.
This Olivier III was now also son and heir of Jeanne Bertran, lady of Tuit, eldest daughter of Guillaume Bertran, lord of Tuit and Thury, a rich Norman heritage.Arch dep Loire-Atlantitique E 165, nr 1 parchment, seal John 1, by Olivier de Clisson, knight, by Olivier de Clisson, squire, parchment in French, many spots Dom Morice, ready. I col 980-981.Morvan, F., Le livre des Ostz (1294). What the lord of Clisson owed for the land of Heric.
Olivier III and Isabeau would eventually have five children:
Olivier IV de Clisson in 1300; Amaury de Clisson, lord of Blandinais; Mahaut de Clisson, Dame des Earts; Gauthier (Garnier) de Clisson and Isabelle de Clisson
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