Puzzle promoter Sam Loyd invented "Saddle the Horse" in 1872. Loyd sold the concept to P.T. Barnum (of Barnum and Bailey circus fame), who handed out millions of them to circus-goers under the name "P.T. Barnumís Trick Mules."
It has since taken on many variations, from clowns on donkeys to witches on black cats, and has delighted generations of puzzle lovers around the world.
The solution is shown in the figures. Please note that the pieces are shown in their orientation that clearly shows the puzzle's idea. Different parts of the cards now form two new galloping horses.