Correspondence, diaries, speech, writings, biographical material, Northrup and Powell family papers, photographs, drawings, and other papers relating to Powell's writings, travel, and personal life. Family papers include correspondence and diaries of Powell's wife, Jessie Northrup Powell, and correspondence of his parents, Edward A. and Lucy Powell. Correspondents include Poultney Bigelow, William Jennings Bryan, Warren G. Harding, J. J. Jusserand, John J. Pershing, Ralph Pulitzer, Theodore Roosevelt, Ellery Sedgwick, and Leonard Wood.