Richard B. Morris, 84, an American history scholar, professor emeritus and editor of the “Papers of John Jay.” Morris’ career spanned more than 60 years, half of them teaching at Columbia University. His more than 40 books included “The Peacemakers: The Great Powers and American Independence” and “The Forging of the Union: 1781-1789.” At the time of his death, Morris was at work on the seventh edition of “The Encyclopedia of American History,” of which he was editor. He was also working on the last two volumes of the four-volume “Papers of John Jay,” America’s first chief justice. Morris was an adviser to Presidents Lyndon B. Johnson and Richard M. Nixon on historical matters. He became a professor emeritus at Columbia in 1973. In New York on Friday of skin cancer.