Born in Melbourne, Quebec, in 1880, he started in films in the Biograph Company of New York, and later opened Keystone Studios in Edendale, California in 1912. Keystone possessed the first fully enclosed film stage, and Sennett became famous as the originator of slapstick routines such as pie-throwing and car-chases, as seen in the Keystone Cops films. He also produced short features that displayed his Bathing Beauties, many of whom went on to develop successful acting careers.
Sennett's work in sound movies was less successful, and he was bankrupted in 1933. He was presented with an honorary Academy Award for his contribution to film comedy.