The main portion of the collection is made up of letters, documents, notes, manuscript and typescript articles and speeches, and scrapbooks and notebooks which are contained in 270 envelopes, folders, manuscript boxes, and bundles. Another 153 bundles, boxes, folders, and envelopes are devoted chiefly to clippings, tear sheets, pamphlets, and books and other printed matter. Proofs of the printing plates for one of Mr. Bancroft's works on Carl Schurz are preserved in eleven envelopes. Pictorial material includes two envelopes of photographs, one envelope of photostats, thirty-four photographs, and eighty-five framed photographs, many with manuscript letters by or relating to the subject of the photograph. The collection is rich in the papers and personal correspondence of Frederic Bancroft and includes notes and various other source materials for his books dealing largely with African Americans, the South, the Civil War, Seward, Calhoun, and the life and work of Carl Schurz. Also, a wealth of material by and about Edgar Bancroft (1857-1925), Frederic's brother and U.S. ambassador to Japan.

Historian, archivist, social activist, and Roman Catholic priest, Browne taught at Catholic University of America (where he also served as University Archivist); St. Joseph's Seminary, Yonkers, N.Y.; Cathedral College; and Rutgers University. He was active in community affairs in New York and Paterson, N.J. His primary research interests were John Hughes, first archbishop of New York, and labor and church history.

Papers of the Jay family and of those families related to the Jay family, including Bruen, Butterworth, Chapman, Clarkson, Dawson, Du Bois, Field, Iselin, McVickar, Mortimer, O'Kill, Pellew, Pierrepont, Prime, Robinson, Schieffelin, Von Schweinitz, Sedgwick, and Wurts. In addition to family and personal matters, the correspondence deals with anti-slavery, New York State civil service, repeal of the Missouri Compromise, the Civil War, the Blair Bill, international affairs, and New York City and State politics and government. There are letters from numerous prominent persons including George Bancroft, F.A.P. Barnard, Bismarck, William Cullen Bryant, Aaron Burr, James Fenimore Cooper, Ralph Waldo Emerson, Hamilton Fish, Albert Gallatin, Horace Greeley, Nathaniel Hawthorne, Oliver Wendell Holmes, Washington Irving, Frances Anne Kemble, Jenny Lind, Henry W. Longfellow, Seth Low, James Russell Lowell, John Stuart Mill, Alice Duer Miller, Clement Clarke Moore, J.P. Morgan, Thomas Nast, Commodore Matthew Perry, Franklin D. Roosevelt, Theodore Roosevelt, Elihu Root, Carl Schurz, William H. Seward, William T. Sherman, Charles Sumner, and John Greenleaf Whittier.

Miscellaneous papers of the Morgan family. Correspondents include Cornelius N. Bliss, Charles Foster, Benjamin Harrison, Temple R. Hollcroft, Herbert Hoover, Levi P. Morton, William H. Seward, and members of the Morgan family. Also, early land deeds and newspaper clippings.