Henri Eugène Philippe Louis d'Orléans, Duke of Aumale was a leader of the Orleanists, a political faction in 19th-century France associated with constitutional monarchy. He was born in Paris, the fifth son of King Louis-Philippe I of the French and Maria Amalia of Naples and Sicily and used the title Duke of Aumale.

Orléanist was a 19th-century French political label originally used by those who supported a constitutional monarchy expressed by the House of Orléans. Due to the radical political changes that occurred during that century in France, three different phases of Orléanism can be identified:The "pure" Orléanism: constituted by those who supported the constitutional reign of Louis Philippe I (1830–1848) after the 1830 July Revolution, and who showed liberal and moderate ideas. The "fusionist" Orléanism: the movement formed by pure Orléanists and by those Legitimists who after the childless death of Henri, Count of Chambord in 1883 endorsed Philippe, Count of Paris, grandson of Louis Philippe, as his successor. The fusion drove the Orleanist movement to more conservative stances, emphasising French nationality and Catholicism. The "progressive" Orléanism: the majority of "fusionists" who, after the decline of monarchist sentiment in the 1890s, joined into moderate republicans, who showed progressive and secular-minded goals, or into Catholic rally, like the Liberal Action.