The Night Watch, 1642 by Rembrandt van Rijn, The Rijksmuseum, Amsterdam.
Called the Night Watch in modern times, the original title of this work Company of Captain Frans Banning Cocq and Lieutenant Willem van Ruytenhurch was a reference to its main characters. The "golden girl" in the background is a mystery. Considering the very fine clothing she wears, she is assumed to be more than a servant. Also her resemblance to Rembrandt's wife has been noted. The final misinterpretation lies in the name of the work, it was not painted as a night image, but had been covered in layers of brown varnish until it was restored after WW II.
