Gawky, loose-limbed Al St. John performed from childhood with his family in vaudeville and burlesque around his home state of California, perfecting an athletic bicycle act that would stand him in good stead for the remainder of his career. Despite his parents' misgivings about "the flickers," St. John was persuaded to enter films by the success of his uncle, Mack Sennett star Roscoe "Fatty" Arbuckle. St. John became a "Keystone Kop" in that famous congregation's very first film, The Bangville Police (1913), supported Charles Chaplin and Marie Dressler in the feature comedy Tillie's Punctured Romance (1914), and then followed Arbuckle to Comique, where he and the young Buster Keaton functioned as "second bananas" to the hefty star. On his own, St. John starred in Educational comedies (one, The Iron Mule , directed by his now disgraced uncle under the pseudonym of William Goodrich), all along developing his patented rube personality complete with oversized overalls and porkpie hat.
St. John himself later claimed that a deal with the Fox company went sour and that he suddenly found himself more or less blacklisted by the major studios. He did appear in one of Roscoe Arbuckle's comeback shorts, Buzzin' Around (1933), but by the mid-'30s he seemed all washed up. To keep food (and, it was rumored, quite a bit of spirits) on the table, St. John switched gears and began pursuing a career in independently produced B-Westerns. He played a variety of characters, both major and minor, before almost accidentally stumbling over the particular role that would sustain him for the rest of his career and make him perhaps the favorite sidekick among kids -- that of the limber, baggy-pants braggart Fuzzy Q. Jones.