Mickey’s “official” birthday changed dates seemingly every year for decades following 1928. In 1933, Walt himself proclaimed, “Mickey Mouse will be five years old on Sunday. He was born on October 1, 1928. That was the date on which his first picture was started, so we have allowed him to claim this day as his birthday.” That date wouldn’t last. Ranging from late September to December, Mickey’s birthday was often altered to conform to specific promotions. It wasn’t until 1978 that Dave Smith, the founder of the Disney Archives, determined that the premiere of Steamboat Willie was truly Mickey Mouse’s first public appearance, therefore his date of birth.
