Gaston d'Orléans was born at the château de Fontainebleau and was given at birth the title of duc d'Anjou. In 1626, at the time of his marriage to the young duchesse de Montpensier, he received in appanage (with their respective titles) the dukedoms of Orléans[1] and Chartres, and the county of Blois[2]. He had nominal command of the army which besieged La Rochelle in 1628[3][4], having already entered upon that course of political intrigue which would occupy the remainder of his life.
On two occasions he had to leave France for conspiring against the government of his mother and of Cardinal Richelieu; and after waging an unsuccessful war in Languedoc, he took refuge in Flanders.
Reconciled with his brother Louis XIII, he plotted against Richelieu in 1635, fled from the country, and then submitted to the king and the cardinal.
Soon afterwards the same process repeated itself. Orléans stirred up Cinq-Mars to attempt Richelieu's murder, and then deserted his unfortunate accomplice (1642). In 1643, on the death of Louis XIII, Gaston became lieutenant-general of the kingdom, and fought against Spain on the northern frontiers of France; he was created duc d'Alençon in 1646. However, during the wars of the Fronde (1648–1653), he passed with great facility from one side to the other.
Anne Marie Louise d'Orléans, duchesse de Montpensier (1627–1693), Mademoiselle de Montpensier, the future Grande Mademoiselle, (to distinguish her from Mademoiselle, the daughter of Monsieur, Louis XIV's brother),
He also had an illegitimate son by Louise-Roger de La Marbelière:
Jean Louis bâtard d'Orléans, comte de Charny, (1638, Tours-1692, Spain).
Later life
After the death of his brother Louis XIII in 1643, Gaston's nephew became Monsieur. To differentiate one "Monsieur" from the other, Gaston, the uncle, was called Le Grand Monsieur and Philippe, duc d'Anjou, his nephew and brother of the new king Louis XIV, was called Le Petit Monsieur.
After the Fronde, Gaston was exiled by Mazarin to Blois in 1652, and remained there until his death. On his death all his Orléans titles went to Le Petit Monsieur, the new and only Monsieur, and duc d'Orléans.