From The Road to Oz by L. Frank Baum, 1909.

From The Patchwork Girl of Oz by L. Frank Baum and illustrated by John R. Neil, 1913.

Here's a precursor to MGM's Cowardly Lion of Oz, from Le Grand Siècle by Émile Bourgeois, 1896.

From The Cowardly Lion of Oz by Ruth Plumly Thompson and illustrated by John R. Neill, 1923.

From The Scarecrow of Oz by L. Frank Baum, 1915.

From The Magic of Oz by L. Frank Baum and illustrated by John R. Neill, 1919.

Here's a precursor to Dorothy and Toto, eight years before the first Oz book was published, from Old Plaistow by John Spencer Curwen (1892).

From Dorothy and the Wizard in Oz by L. Frank Baum, 1908.

From The Road to Oz by L. Frank Baum, 1909.

Eighty-four years before Tim Burton introduced Jack Skellington in The Nightmare Before Christmas, L. Frank Baum's The Road to Oz (1909) featured another pumpkin-head named Jack.

From The Scarecrow of Oz by L. Frank Baum, 1915.