La Rochefoucauld-Liancourt, François Alexandre Frédéric, duc de (
älĕksäN'drə frādārēk' dük də lä rôshfūkō'-lyäNkūr') , 1747–1827, French social reformer. Before the French Revolution he established a model farm, two factories, and a trade school on his estate, and in the Constituent Assembly he urged the necessity of public welfare. A royalist during the French Revolution, he was forced to flee to England in 1792. From there he traveled to the United States where he wrote
Voyage dans les États-Unis d'Amérique (1799). Upon his return to France (1799), he resumed his philanthropic activities, working especially for health, educational, and economic reforms.