Empress Carlota of Mexico

Carlotta was a young royal, married to an up-and-coming fellow royal (and rumored relative of Napoleon), Maximilian, when she took on moving to Mexico as the new French-installed Empress of Mexico. Her husband's rule was not, however, welcomed, and when Carlotta returned to Europe she had what her secretary termed "a grave attack of mental aberration." It lasted for over sixty years. Read more about the sad outcome of this imperial power play for her husband and for herself: Empress Carlota of Mexico