Its subject is identified with reasonable security as Cecilia Gallerani, the mistress of Lodovico Sforza,”Ludovico il Moro”, Duke of Milan. Leonardo met Cecilia Gallerani in Milan in 1484 while both were living in Castello Sforzesco, the fortress-palace of Duke Lodovico Sforza. She was the Duke’s mistress; young and beautiful (she was only 17 years old), Cecilia played music and wrote poetry. Several interpretations of the significance of the ermine in her portrait are possible. Pet ermines were associated with the aristocracy and ermines were emblems of purity that would face death rather than soil their pristine coats and a personal device of Ludovico il Moro, who had been invested with the Order of the Ermine in 1488, so its association with Cecilia could have had multiple meanings. Alternatively, it could be a pun on her name (the Greek for ermine is galay). Strictly speaking, the animal in the painting appears to be not an ermine but a white ferret, a type favored in the Middle Ages because of the ease of seeing the white animal in thick undergrowth. The sitter’s hair is confined tightly to her head under a very fine net veil with a woven border of gold-wound threads.