The Last Voyage
This rather grim painting depicts the English explorer Henry Hudson, who was set adrift in a boat with his son, after his crew mutinied, and never seen again. Hudson explored the region around modern New York City while looking for a western route to the Orient under the auspices of the Dutch East India Company. He discovered the Hudson River and laid the foundation for Dutch colonization of the region.
Not a very pleasant subject but an unusual square composition (unless this is a detail).