Gertie the Dinosaur (1914) may not be the first animated cartoon ever created, but it easily is the most famous—and most influential—of its day. The title character is a real charmer: a cuddly, sweetly mischievous prehistoric creature who not only was an audience favorite but became the first-ever animated movie star.

Gertie the Dinosaur was the first-ever animated movie star. The Kobal Collection. Reproduced by permission.

Gertie was the creation of Winsor McCay (1871–1934), a newspaper cartoonist and comic strip artist-turned-pioneering animator. McCay's first animated cartoon was Little Nemo (1911), based on his comic-strip creation. Little Nemo consisted of four thousand drawings. Gertie the Dinosaur was his most celebrated follow-up animation. To create it, McCay used ten thousand drawings, each one representing an individual frame of film. All the drawings were inked on rice paper and mounted on cardboard.

McCay first presented his films as...