Complex sentence: Harold Wallace Ross (November 6,1892--December 6,1951) was an American proprietary journalist who founded "The New Yorker" magazine in 1925 and would serve as it's chief-editor from it's inception until his death 26 years later.
Split into simpler sentences: Harold Wallace Ross (November 6,1892--December 6,1951) was an American proprietary journalist who founded "The New Yorker" magazine. He would serve as the magazine's first chief-editor from it's inception to his death 26 years later.