second son of King Louis-Philippe. After the abdication of his father in 1848 he tried until 1871 to unite exiled royalists and restore the monarchy.

A colonel of cavalry from 1826, Nemours was elected king of the Belgians in 1831, but Louis-Philippe refused that crown in his son's name. Nemours was present at the French siege of Antwerp in 1832 and later accompanied three expeditions to Algeria (1836, 1837, and 1841). His conservatism antagonized the liberal opposition in France, and in 1840 the Chamber of Deputies refused to grant the dowry proposed for his marriage to Princess Victoria of Saxe-Coburg-Gotha. In 1842 the death of his elder brother, Ferdinand, Duke d'Orléans, made Nemours the prospective regent of France in the event of Louis-Philippe's dying before Ferdinand's son Louis-Philippe-Albert, Count de Paris, should have come of age. But again his conservatism and unpopularity worked against him, and certain factions desired that, instead of Nemours, Ferdinand's wife, the Duchess d'Orléans (Helena of Mecklenburg-Schwerin), become regent for her son.

On the outbreak of revolution in 1848, Nemours organized the defense of the Tuileries to cover King Louis-Philippe's escape and then tried to accompany the Duchess d'Orléans to the Chamber of Deputies to press her son's claims. Instead, the deputies proclaimed the Second Republic. Nemours, the duchess, and her children fled, and Louis-Philippe abdicated.

In exile in England, Nemours sought to effect a reconciliation between the house of Orléans and the Count de Chambord, the exiled grandson of Charles X and a pretender to the French throne, as the indispensable preliminary to a restoration of the monarchy in France. After the Franco-German War and the removal of the legal disabilities of the French princes (1871), Nemours returned to France and was restored to his army rank of divisional general. An attempt by the Count de Chambord to reunite France under a Bourbon monarchy failed, and Nemours's hopes of a restoration were dashed.