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The first Daffy Duck cartoon, as many people know, is of course Porky's Duck Hunt first released on April 17, 1937.
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As pleased as Tex was that this duck now called Daffy from his cartoon was doing well, I think he was hoping for another creation of his to become a star. That same year, Tex made a cartoon called Egghead Rides Again starring his other creation Egghead.
It looks like Tex deliberately put the character's name in the title so that audiences would catch on to him quicker. Also he hoped that adding the phrase "rides again" would give some validity to Egghead. People would read that and subconsciously think that Egghead had 'ridden before' as in many cartoons about him had been made before. You can also tell Tex really wanted Egghead to go far by the next Daffy Duck cartoon:
It's actually called Daffy Duck and Egghead and was released on January 1, 1938. It looks like Tex was hoping that some of Daffy's popularity would be transferred to Egghead just by proximity and association.
Of course, Daffy would continue to be a popular character while Egghead would fade into obscurity without ever really developing any kind of following.
Later in 1938, Tex would release his third and final Daffy cartoon:
Legend has it that the pig director character in this cartoon, "Von Hamburger", was a caricature of a real director who was brought from Germany to Warner Bros. to make live action movies. Apparently he was an egotistical jackass who constantly ordered people around and made demands of everybody.
I guess Tex Avery felt that unleashing Daffy Duck into his personal space would be a suitable punishment for him and bring him and his ego down so many pegs.
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Animator and animation historian Mark Kausler has talked about his dealings with Tex Avery back when Tex was still around. One anecdote of his is that he would constantly write fan letters to Tex with a drawing of Screwy Squirrel in the top corner. These letters received no replies. Then, he sent a fan letter with Droopy drawn on the side which did receive a reply of something "thank you, I appreciate it". So obviously Tex had no qualms about expressing his low opinion of his squirrel creation. But I personally haven't heard Tex say a thing about Daffy, good or bad.
Oh well, I guess I'll leave that as a mystery for the ages. So now, I'll end this post with Tex Avery's cartoon that started it all. Happy 109th birthday Tex.