The only daughter of Leopold I, king of the Belgians, and Princess Louise of Orléans, Carlota married at age 17 the archduke Maximilian, brother of the emperor Francis Joseph of Austria. They lived as the Austrian regents in Milan until 1859, when Austria lost control of Lombardy. In May of 1864 she accompanied Maximilian to Mexico to accept the Mexican crown offered him by Napoleon III of France. The ambitious Carlota welcomed her authority in Mexico, learned Spanish, and became genuinely interested in Mexican history, art, and culture. When in 1866 Napoleon withdrew his troops in the face of Mexican resistance and U.S. opposition, she sought assistance for her husband's regime in Paris and Vienna and finally in Rome from the pope. Upon the failure of her efforts, she exhibited paranoia and other signs of mental illness. She never returned to Mexico. After the Mexicans executed her husband the following year, her mental illness worsened, and she spent the rest of her life in seclusion in castles at Laeken, Belg., and near Trieste, Italy.