Complex sentence: The speech may have been invented by Eustace Mullins and appeared in the early 1950s racist newsletter, Common Sense, ("A Newspaper Upholding Christianity and Patriotism") published by Conde McGinley.
Split into simpler sentences: The speech may have been invented by Eustace Mullins. It appeared in the early 1950s right-wing newsletter, Common Sense, ("A Newspaper Upholding Christianity and Patriotism") published by Conde McGinley.