Napoléon Joseph Charles Paul Bonaparte (9 September 1822 – 17 March 1891), usually called Napoléon-Jérôme Bonaparte or Jérôme Bonaparte, was the second son of Jerome, King of Westphalia, youngest brother of Napoleon I, and his second wife Catharina of Württemberg. An outspoken liberal, he became the "de facto" head of the House of Bonaparte from 1879 to his death. He was not considered a legitimate pretender to the throne by many Bonapartists, due to his father's previous marriage without divorce. They instead preferred his son Victor. From the 1880s he was one of the stronger supporters of General Georges Boulanger, together with other monarchist forces.