I chose Ollie Johnston because he was one of Disney's original animators. He animated many recognizable charactors from Disney movies such as Snow White and the Seven Dwarfs, One Hundred and One Dalmations, The Jungle Book, Bambi, and Lady and the Tramp.
He was such an influencial animator that other animators paid tribute to his career by placing him in their movies as a chameo character. He appeared as an old man in The Incredibles along with fellow animator Frank Thomas and as a train conductor in The Iron Giant. He appeared as Rufus the cat in The Rescuers, his last full movie for Disney.
He also defined the 12 Principles of Animation in a guidebook for the early animators at Disney. These principles gave Disney characters their classic Disney look and believability.