[7] Jay Ward and his business partner Alex Anderson created Bullwinkle for The Frostbite Falls Review, a storyboard idea which was never developed into a series.

They gave him the name "Bullwinkle Jay Moose" after Clarence Bullwinkel, who owned a Ford[8][9] dealership at College and Claremont, in Oakland, California,[10][11] because they thought it was a funny name.

Also, in contemporary promotion art, Bullwinkle's antlers are a yellow in contrast to the rest of his body; originally they were brown.

In seasons 1 and 2, he makes reference to having an Uncle Dewlap, who bequeathed Bullwinkle vast amounts of wealth (in the form of a cereal boxtop collection and an Upsidaisium mine); he also has a large petty cash stockpile hidden in his mattress that he accumulated delivering newspapers (as revealed in "The Last Angry Moose").

Bullwinkle was noted for being well-intentioned, but also quite foolish, which made for a source of jokes and plot devices during the show's run.

His apparent lack of brilliance also had positive side effects, making him immune to mind-numbing chemicals in "Goof Gas Attack" and being the only person able to properly handle the Kirwood Derby hat in "Missouri Mish Mash".

Bullwinkle also hosted other segments of the program, including: "Mr. Know-It-All," where he tried to demonstrate his supposed (albeit nonexistent) expertise on a variety of subjects, such as disarming bombs, curing hiccups or escaping from Devil's Island; "Bullwinkle's Corner", where the moose would attempt to read poetry, notably "I Wandered Lonely as a Cloud" (The Daffodils) of William Wordsworth; and various interstitial drop-ins.

The show's soundtracks would mark one of Bill's final roles as Bullwinkle and Dudley Do-Right, as he died of a heart attack in 1985.

He would later reprise the role in the form of WYME TV animated skits Wilson personally produced for Bullwinkle's Restaurants around 1996.