Complex sentence: Martin J. Quigley, Sr. (1890--1964), a renowned publisher and journalist of film magazines and founder of motion picture trade periodicals, including "Exhibitors Herald" that he turned into an important national trade paper for the film industry.
Split into simpler sentences: Martin J. Quigley, Sr. (1890--1964) was an American publisher, editor and film magazine journalist. He founded "Exhibitors Herald", which became an important national trade paper for the film industry.