Also known as the Portrait of the Unknown Woman, or Lady with an Ermine. It may be of Lucrezia Crivelli, who was a mistress of Ludovico Sforza. Or it may be Cecilia Gallerani, also a mistress of Ludovico. Or it may be a painting of a wife or daughter of an ironmonger (ferronnier) who was also the mistress of François I, king. The husband, infects himself with syphilis, so he can infect the king with syphilis. Because of all the confusion, no wonder its called "Portrait of an Unknown Woman" as well.