He was an animator at Walt Disney Studios from 1935 to 1978, and became a directing animator beginning with Pinocchio, released in 1940. He contributed to most Disney animated features, including Snow White and the Seven Dwarfs, Fantasia, and Bambi. His last full work for Disney came with The Rescuers, in which he was caricatured as one of the film's characters, the cat Rufus.
Johnston co-authored, with Frank Thomas, the reference book Disney Animation: The Illusion of Life, which contained the 12 basic principles of animation. This book helped preserve the knowledge of the techniques that were developed at the studio.
In a likely reference to the book, the Adventures of the Gummi Bears episode "Light Makes Right" contains a scene featuring the children's book Tall Tales of The Gummi Bear, which features a page with the words "Two of Gummi's famous Nine Old Bears, Frank and Ollie", honoring both animators with a blink-and-you-miss-it inside joke.
Born in Palo Alto, California, Johnston attended Stanford University, where he worked on the campus humor magazine Stanford Chaparral with fellow future animator Frank Thomas. He then transferred to the Chouinard Art Institute in his senior year.
Ollie married a fellow Disney employee, ink and paint artist Marie Worthey, in 1943. Marie Johnston died May 20, 2005. Ollie's lifelong hobby was live steam trains. Starting in 1949, he built a 1" scale backyard railroad, with three 1/12 scale locomotives, now owned by his sons. This railroad was one of the inspirations for Walt Disney to build his own backyard railroad, the Carolwood Pacific Railroad, which again inspired the building of the railroad in Disneyland. Ollie was a founding Governor of the Carolwood Pacific Historical Society along with his fellow Disney animator and railfan, Ward Kimball. The 1/4 scale Victorian depot from Ollie's backyard was moved and restored to a location near Walt Disney's Carolwood Barn at the area of the Los Angeles Live Steamers club in Griffith Park, Los Angeles.
In the 1960s Ollie acquired and restored a full-size narrow-gauge Porter steam locomotive, which he named the "Marie E." On May 10, 2005 it ran during a private early morning event on the Disneyland Railroad. To date, the only time The Walt Disney Company permitted outside railroad equipment to run at any Disney Resort. This engine and its consist were sold to John Lasseter of Pixar Animation Studios fame. The engine is fully operational and ran at the Santa Margarita Ranch near San Luis Obispo, California in May 2007.
Brad Bird paid a tribute to Ollie Johnston with an animated cameo of Johnston in the 2004 Pixar film, The Incredibles, as well as a cameo in his 1999 film, The Iron Giant, where he played a train engineer.
On November 10, 2005, Ollie Johnston was among the recipients of the prestigious National Medal of Arts, presented by President George W. Bush in an Oval Office ceremony.
Characters animated by Johnston
- Snow White and the Seven Dwarfs - Dopey
- Pinocchio - Pinocchio
- Fantasia - Cupids in "Pastoral Symphony", Centaurettes by the lake
- Bambi - Bambi, Thumper
- The Three Caballeros - "The Flying Gauchito", Donald Duck, Panchito Pistoles, Jose Carioca
- Make Mine Music - "Casey at the Bat", "Peter and the Wolf"
- Song of the South - Br'er Rabbit, Br'er Fox, Br'er Bear
- Melody Time - Johnny Appleseed and Johnny's Guardian Angel in "Johnny Appleseed", "Little Toot"
- The Adventures of Ichabod and Mr. Toad - Ratty, Moley, Macbadger, Trial Scene, Ichabod Crane, Brom Bones, Katrina
- Cinderella - Evil Stepsisters, Lackey
- Alice in Wonderland - Alice, King of Hearts
- Peter Pan - Wendy Darling, Mr. Smee
- Lady and the Tramp - Lady, Jock, Trusty
- Sleeping Beauty - Three Good Fairies
- One Hundred and One Dalmatians - Pongo, Perdita, Puppies, Nanny Cook
- The Sword in the Stone - Wart, Merlin, Archimedes
- The Jungle Book - Mowgli, Baloo, Bagheera, Shanti
- The Aristocats - Duchess, Thomas O'Malley, Kittens, Amelia, Abigail, Uncle Waldo
- Robin Hood - Prince John, Sir Hiss, Robin Hood, Little John, Maid Marian
- The Many Adventures of Winnie the Pooh - Winnie the Pooh, Piglet, Rabbit, Kanga, Roo
- The Rescuers - Bernard, Bianca, Chairman, Rufus the Cat, Penny, Orville the Albatross
- The Fox and the Hound - Young Tod, Young Copper