Isabelle de Beauvau or Isabeau de Beauvau (around 1436–1475) was a French noblewoman, of the Beauvau family, lady of Champigny and de la Roche-sur-Yon, countess of Vendôme by her marriage.
Isabelle was the only child of the marriage between Count Louis de Beauvau (1409-1492) and his first wife, Marguerite de Chambley,[1] a woman of noble birth from Lorraine. Isabelle's lineage made her valuable to René of Anjou, who was dealing with a succession crisis over the duchy of Lorraine. He was trying to strengthen ties with Lorraine's nobility which is why her name appears with those of her mother and Yolande, Duchess of Lorraine, in a handwritten collection of poems by Alain Chartier offered to Marie de Clèves.[2] Other than that not much is known about Isabelle's childhood; her marriage negotiations started before she was eighteen.
Isabelle married John VIII, Count of Vendôme, on 9 November 1454 at Angers,[3] thus becoming the Countess of Vendôme. Isabelle and John had:
Isabelle died giving birth to her last daughter. She is buried in the Saint-George collegiate church in Vendôme, the Bourbon Vendôme necropolis, which has since disappeared. Through her third daughter she was great-grandmother to the French nobility. She is most remembered for the poem by Alain Chartier to Marie of Cleves.