During the first two decades of the twentieth century, comedy was the favorite genre of moviegoers, and no moviemaker was more adept at tickling the funnybones of audiences than Mack Sennett (1880–1960). One of the most famous and everlasting of all his contributions to screen comedy was the Keystone Kops, a fictional gang of well-meaning but hilariously inept policemen. The Keystone Kops have long been synonymous with onscreen slapstick and bungling, chases filled with horseplay, and overall comic chaos.

Sennett was mentor to some of the era's most famous screen comedians, including Charlie Chaplin (1889–1977; see entry under 1910s—Film and Theater in volume 1) and Mabel Normand (1894–1930). He also worked with dozens of other comic actors, including Ford Sterling (1883–1939), Chester Conklin (1888–1971), Hank Mann (1887–1971), Fred Mace (1878–1917), Edgar Kennedy (1890–1948), and Roscoe "Fatty" Arbuckle (1887–1933), all of whom at one time or another were members of the Keystone Kops. The head of...