Hi! The origins and subject of this painting
have been questioned many times through
the years, but the Frick Collection in New York
City displays it as....
The Polish Rider, c. 1655
by Rembrandt van Rijn (1606 - 1669) - Dutch
Oil on canvas
46 x 53 1/8 in. (116.8 x 134.9 cm)
http://collections.frick.org/media/view/Objects/239/3407?t:state:flow=3a65b014-278c-4608-a51f-2b383ccf2240
http://collections.frick.org/view/objects/asitem/items$0040:239
You can read all about the many theories
concerning subject and authorship below...
http://collections.frick.org/view/objects/asitem/search@/0?t:state:flow=3c521696-eba2-4675-8310-bcc646586671
Source:
Art in The Frick Collection by Harry N. Abrams
http://www.nytimes.com/1997/10/24/arts/inside-art.html
http://en.wikipedia.org/wiki/The_Polish_Rider
I hope this helps! :)