Jan Baptist Weenix (1621-1660), a Dutch painter, was the son of an architect and born in Amsterdam. Because of a stroke he could not speak very well, but he very much liked to read books. His mother sent him to a booksellar, who was not able to deal with him. He seemed to be drawing whenever he could.

He first studied under Jan Micker, then in Utrecht under Abraham Bloemaert, again in Amsterdam under Claes Cornelisz. Moeyaert. Between 1643 and 1647 Weenix was in Rome. Arnold Houbraken tells us he had left the house secretly, but his wife, the daughter of Gillis d'Hondecoeter, had traced back him in Rotterdam. Then he was allowed stay away for four months. In that city he was much esteemed and worked for Pope Innocent X. He returned to Amsterdam after four years, while his wife refused to come to Rome.

In 1649 he became master of the guild of St. Luke at Utrecht. In that year he also made a portrait of Rene Descartes. When his brother-in-law Gijsbert d'Hondecoeter died, he trained his son Melchior d'Hondecoeter. He moved to a castle outside Utrecht, to concentrate on his work, where he probably died in 1660.

Weenix, despite his relatively brief career, was a very productive and versatile painter. His favourite subjects were Italian landscapes with large figures among ruins, seaside views, and, later in life, large still life pictures of dead game. Now and then he attempted religious scenes, one of the rare pieces of this kind being the "Jacob and Esau" at the Dresden Gallery. At the National Gallery, London, is a "Hunting Scene" by Weenix, and the Glasgow Gallery has a characteristic painting of ruins. Weenix is represented at most of the important continental galleries, notably at Munich, Vienna, Berlin, Amsterdam, and St Petersburg. His chief pupils were his son Jan, Berchem, and Hondecoeter.