Passage: The Hundred Years' War had begun in 1337 as an inheritance dispute over the French throne, interspersed with occasional periods of relative peace. Nearly all the fighting had taken place in France, and the English army's use of chevauchée tactics (destructive "scorched earth" raids) had devastated the economy. The French population had not regained its former size since the Black Death of the mid-14th century, and its merchants were isolated from foreign markets. Before the appearance of Joan of Arc, the English had nearly achieved their goal of a dual monarchy under English control and the French army had not achieved any major victories for a generation. In the words of DeVries, "The kingdom of France was not even a shadow of its thirteenth-century prototype."The French king at the time of Joan's birth, Charles VI, suffered from bouts of insanity and was often unable to rule. The king's brother Louis, Duke of Orléans, and the king's cousin John the Fearless, Duke of Burgundy, quarreled over the regency of France and the guardianship of the royal children. This dispute included accusations that Louis was having an extramarital affair with the queen, Isabeau of Bavaria, and allegations that John the Fearless kidnapped the royal children. The conflict climaxed with the assassination of the Duke of Orléans in 1407 on the orders of the Duke of Burgundy.The young Charles of Orléans succeeded his father as duke and was placed in the custody of his father-in-law, the Count of Armagnac. Their faction became known as the "Armagnac" faction, and the opposing party led by the Duke of Burgundy was called the "Burgundian faction". Henry V of England took advantage of these internal divisions when he invaded the kingdom in 1415, winning a dramatic victory at Agincourt on 25 October and subsequently capturing many northern French towns. In 1418 Paris was taken by the Burgundians, who massacred the Count of Armagnac and about 2,500 of his followers. The future French king, Charles VII, assumed the title of Dauphin—the heir...

Question: What is the name of the title given to the heir to the throne?
Dauphin