Complex sentence: Beginning as a copyboy at the Chicago Daily News in 1943, Holtzman wrote for the paper through its merger with the Chicago Sun. Holtzman's influence and viewpoints made him something of a legend among newspapermen.
Split into simpler sentences: Beginning as a copyboy at the "Chicago Daily News" in 1943, Holtzman wrote for the paper through its merger with the "Chicago Sun". His influence and viewpoints made him something of a legend among newspapermen.