Correspondence; speeches; legal, business, and financial records; biographical material; clippings; printed matter; and other papers relating chiefly to Stevens's service in the U.S. Congress and to family and business affairs. Subjects include Abraham Lincoln; African American suffrage; African American troops; Andrew Johnson's policies and impeachment; anti-Masonic movement; bank loans; the Civil War; confiscation of Confederate property; conscription; education in Pennsylvania; gold standard; mining of coal and iron ore in Pennsylvania; paper money secured by government bonds; Pennsylvania state and national politics; railroads; Reconstruction; the Republican Party; secession; slavery; states' rights; tariffs; taxation; the treaty to purchase Alaska; the Union Army; the Union Pacific Railroad Company; U.S. Bureau of Refugees, Freedmen, and Abandoned Lands (Freedman's Bureau); the Whig Party; Abdallah, Sultan of Anjouan (Johanna Island), Comoros; and the occupation of Mexico by Maximilian, Emperor of Mexico. Subjects also include Stevens's partnership in J.D. Paxton & Co. (later Stevens & Paxton Co.), Caledonia Iron Works, and the Wrightsville, York, and Gettysburg Railroad Company; and the estate of William Camp.

Correspondents include John Binney, James Buchanan, Salmon P. Chase, W.M. Dent, Oliver James Dickey, F.A. Dockray, John Charles Frémont, Henry Goddard, Horace Greeley, Alexander Hood, Reverdy Johnson, Alexander K. McClure, D. M'Conaughy, Edward McPherson, Lewis Merrill, William Nesbit, William B. Reed, Edward Reilly, Winfield Scott, Dudley Selden, Samuel Shoch, Charles S. Spencer, A.J. Stevens, Simon Stevens, Thaddeus Stevens. Jr., Charles Sumner, John Sweney, and David Wills.