Line of succession to the French throne (Bonapartist) sons, and it seemed unlikely that he would have any due to the age of his wife, Joséphine de Beauharnais. His eventual response was to have his marriage to Josephine annulled and to undertake a second marriage with Roman Catholic rites to Archduchess Marie Louise, daughter of Emperor Francis I of Austria. Their only child was Napoleon, King of Rome, known in exile as "Napoleon II" and as the Duke of Reichstadt. He died unmarried, thereby extinguishing the legitimate descent of Napoleon I. Meanwhile, Napoleon I's older brother, Joseph Bonaparte, recognized upon establishment of the First Empire as first in
Napoleon II Françoise Le Tellier de Montesquiou, a descendant of François-Michel le Tellier, Marquis de Louvois, who was named Governess of the Children of France. Affectionate and intelligent, the governess assembled a considerable collection of books intended to give the infant a strong grounding in religion, philosophy, and military matters. As the only legitimate son of Napoleon I, he was already constitutionally the Prince Imperial and heir apparent, but the Emperor also gave his son the style of King of Rome. Three years later, the First French Empire collapsed. Napoleon I saw his second wife and their son for the last time