Marie de Bourbon (15 October 1605 – 4 June 1627), Duchess of Montpensier, and Duchess of Orléans by marriage, was a French noblewoman and one of the last members of the House of Bourbon-Montpensier. Her parents were Henri de Bourbon, Duke of Montpensier and Henriette Catherine de Joyeuse, Princess of Joinville and Duchess of Joyeuse in her own right.

Marie de Bourbon was born in the château de Gaillon, in Gaillon (Eure department of France), in the former province of Normandy.

Known as Mademoiselle de Montpensier before her marriage, she was the Duke and Duchess of Montpensier's only child. At the age of two, she had been engaged to the second son of Henry IV of France, Nicolas Henri de France, Duke of Orléans, but he died at the age of four in 1611. She was then betrothed to his brother, Gaston de France, Duke of Orléans, the younger brother of king Louis XIII, and the heir presumptive to the throne of France.

At the death of her father, in 1608, Marie became the Duchess of Montpensier in her own right; the Duchy was one of the oldest in France having been elevated from a County in 1539. Marie was a descendant of John II of France, of the House of Valois and of Saint Louis.

Because of the Montpensier's fortune, of which Marie was the only heiress, and despite the aversion shown by Gaston toward this arranged marriage, Louis XIII and Richelieu were determined the marriage would take place.

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