Family and general correspondence, letterbooks, diaries, notebooks, scrapbooks, clippings, newspapers, printed matter, maps, drawings, photographs, and other papers. Includes letters from Morse to his family describing his studies in England during the War of 1812 and his subsequent struggle to support himself as a portrait painter in the United States and commenting on American, British, and European art; correspondence and other papers relating to his invention of the telegraph, law suits over patents, and his dispute with Joseph Henry who also claimed to have invented the telegraph; diaries (chiefly 1829-1831) recording his travels in Italy and elsewhere in Europe and his observations on art and architecture; and papers of Ludwig Clausing (also known as Lewis or Louis), a German immigrant to the United States whom Morse befriended. Other topics include abolitionism, Anti-Catholicism, the nativist movement, and the science of photography.

Correspondents include Louis Agassiz, Washington Allston, J. G. Chapman, DeWitt Clinton, Thomas Cole, John S. Cogdell, James Fenimore Cooper, Ezra Cornell, Louis Daguerre, Jeremiah Evarts, Cyrus Field, Horatio Greenough, Thomas Smith Grimké, Joseph Henry, Amos Kendall, Charles B. King, Marquis de Lafayette, Charles Robert Leslie, Jedidiah Morse, Lucretia Pickering Walker Morse, Sidney E. Morse, Richard Rush, William H. Seward, Francis O. J. Smith, Gilbert Stuart, Benjamin West, and William Wilberforce.