Silent movies were gradually fading away in the 30's. One of the last ones was a very short animated cartoon starring The Lone Ranger. While we don't know the exact year it was made, what we do know is that Roy Meredith directed, and presumably also produced, "The Masked Rider", a compact tale detailing the Ranger and Tonto's pursuit of cattle rustlers, clocking in at just under 3 minutes.
The Ranger would be parodied in animation by Warner Bros when Porky Pig met "The Lone Stranger", then Hugh Harman created "The Lonesome Stranger". Even Mickey Mouse got in on the act at Disney.
As we all know, the first animated series for television bowed on CBS 50 years ago, and we know the rest of that story.