and kept him in her own castles, usually those in the Loire Valley, where Charles received Joan of Arc. Yolande arranged the marriage of Charles to her daughter Mary of Anjou, thus becoming Charles' mother-in-law. This led to Yolande's personal, and crucial, involvement in the struggle for the survival of the House of Valois in France. Yolande's marriage to Louis II of Anjou, at Arles in December 1400, was arranged as a part of long-standing efforts to resolve contested claims upon the kingdom of Sicily and Naples between the houses of Anjou and Aragon. Louis spent much of his life fighting in Italy for his claim to the Kingdom of Naples. In France, Yolande was the Duchess of Anjou and the Countess of Provence. She preferred to hold court in Angers and Saumur. She had six children, and through her second son René was the grandmother of Margaret of Anjou, the wife of King Henry VI of England. With the victory of the English over the French at the Battle of Agincourt in 1415, the Duchy of Anjou was threatened. The French king, Charles VI, was mentally ill and his realm was in a state of civil war between the Burgundians and the Orleanists (Armagnacs). The situation was made worse by an alliance between the Duke of Burgundy, John the Fearless, the English, and the French queen, Isabeau of Bavaria, who submitted to the Duke of Burgundy's scheme to deny the crown of France to the children of Charles VI. Fearing the abusive power building behind the Duke of Burgundy, Louis II had Yolande move with her children and future son-in-law, Charles, to Provence in southern France. The Dauphin In the years 1415 and 1417, the two oldest surviving sons of Charles VI of France died in quick succession: first Louis, then Jean. Both brothers had been in the care of the Duke of Burgundy. Yolande was the protectress of her son-in-law, Charles, who became the new Dauphin. She refused Queen Isabeau's orders to return Charles to the French Court, reportedly replying, "We have not nurtured and cherished this one for you to make him die like his brothers or to go mad like his father, or to become English like you. I keep him for my own. Come and take him away, if you dare." (according to Jehan de Bourdigné) On 29 April 1417, Louis II of Anjou died