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.

The 4th House of Orléans, sometimes called the House of Bourbon-Orléans to distinguish it, is the fourth holder of a surname previously used by several branches of the Royal House of France, all descended in the legitimate male line from the dynasty's founder, Hugh Capet. The house was founded by Philippe I, Duke of Orléans, younger son of Louis XIII and younger brother of Louis XIV, the "Sun King".