In 1626, at the time of his marriage to the young Marie de Bourbon, Duchess of Montpensier, he received in appanage (with their respective titles) the duchies 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 a course of political intrigue that would occupy the remainder of his life.

Because he had not obtained the prior permission of his elder brother, the king – one of his many acts of defiance – the couple could not appear at the French court and the marriage was kept secret.

But in November of that year, Henri II, Duke of Montmorency, on his way to the scaffold, betrayed Gaston, his former co-conspirator, and Louis XIII and Richelieu learnt of the elopement.

The king had his brother's marriage declared null and void by the Parlement of Paris in September 1634 and, despite the protest of Pope Urban VIII,[6] the Assembly of the French clergy held in September 1635 that a prince du sang could enter matrimony only with permission of the king – consistent with French sovereignty and custom.

It was not until Louis XIII was on his deathbed in May 1643 that he accepted his brother's plea for forgiveness and authorized his marriage to Marguerite, whereupon the couple undertook nuptials for the third time in July 1643 before the Archbishop of Paris at Meudon, and the Duke and Duchess of Orléans were finally received at court.

After the death of his mother in 1642, Gaston was bequeathed the Luxembourg Palace, which became the couple's Parisian residence under the name Palais Orléans once they were restored to royal favour.