Louis, Duke of Brittany, Dauphin of France , was the first son of Louis of France, Duke of Burgundy, and Marie Adlade of Savoy.
Eldest surviving son of the Dauphin, he was a fils de France. Louis was born at Versailles to the Duke and Duchess of Burgundy. He was created the Duke of Brittany succeeding his late brother Louis that was the first to hold the title in 200 years. At the time of his birth Louis was the thirdinline heir to his greatgrandfather, King Louis XIV, following his father and grandfather, Louis, le Grand Dauphin. He was preceded in birth by an elder brother, also named Louis, who was born in 1704 and died in infancy the following year.
Source: Wikipedia