| Jean d'Orléans | |
| Duke of Guise | |
| Succession: | Head of the House of Orléans |
| Reign: | 28 March 1926 – 25 August 1940 |
| Reign-Type: | Tenure |
| Predecessor: | Prince Philippe, Duke of Orléans |
| Successor: | Henri, Count of Paris |
| Birth Date: | 4 September 1874 |
| Birth Place: | Paris, France |
| Death Place: | Larache, Morocco, Spain |
| Full Name: | Jean Pierre Clément Marie d'Orléans |
| Father: | Prince Robert, Duke of Chartres |
| Mother: | Princess Françoise of Orléans |
| Issue: | Isabelle, Princess Pierre Murat Françoise, Princess Christopher of Greece and Denmark Princess Anne, Duchess of Aosta Prince Henri, Count of Paris |
| House: | Orléans |
| Religion: | Roman Catholic |
| Signature: | Jean_duke_of_guise_1900_signature.png |
Prince Jean of Orléans, Duke of Guise (Jean Pierre Clément Marie; 4 September 1874 - 25 August 1940), was the third son and youngest child of Prince Robert, Duke of Chartres (1840–1910), grandson of Prince Ferdinand Philippe and great-grandson of Louis Philippe I, King of the French. His mother was Françoise of Orléans, daughter of François, Prince of Joinville, and Princess Francisca of Brazil. He was the Orléanist pretender to the throne of France as Jean III.
In 1926 at the death of his cousin and brother-in-law Philippe, Duke of Orléans, claimant to the defunct throne of France as "Philip VIII", Jean was recognised by his Orléanist supporters as titular king of France with the name "Jean III".
Jean was an amateur historian and archeologist, who lived with his family in a large farm near Rabat, Morocco. Following his "ascension" as Orléanist pretender, he and his eldest son were legally forbidden from ever entering France again, due to an 1886 edict which condemned the heads of Bourbon & Bonaparte dynasties, as well as their heirs apparent, to exile.[1]
Jean died in Larache, Morocco, in 1940. He was succeeded as Orléanist claimant to the defunct French throne by his only son, Henri d' Orléans, Count of Paris.
In 1899, Jean married his first cousin, Isabelle d'Orléans (1878–1961). She was the younger sister of Philip VIII, and the daughter of Philip VII and Marie Isabelle d'Orléans.
They had four children: