Correspondence covering Washburne's career as a member of Congress in the Civil War era, 1853-1869, and as minister to France, 1869-1877. Subjects include Abraham Lincoln, appropriations, commerce, Commune de Paris, Franco-Prussian War, Germany, German residents of France, Ulysses S. Grant, seige of Paris, 1870-1871, Reconstruction, France's Third Republic, and Whig politics in Illinois and the U.S.

Correspondents include Cyrus Aldrich, Isaac Newton Arnold, Adam Badeau, George Bancroft, Otto Fürst von Bismarck, James Gillespie Blaine, William Harrison Bradley, Salmon P. Chase, J. C. Bancroft Davis, John A. Dix, William Maxwell Evarts, Jules Favre, Hamilton Fish, Antoine Alfred Agénor duc de Gramont, Ulysses S. Grant, Horace Greeley, Murat Halstead, John Jay, Joseph Medill, Benjamin Moran, Edwards Pierrepont, Charles Henry Ray, Daniel Richard, Robert Cumming Schenck, John Sherman, William T. Sherman, Daniel Edgar Sickles, Charles L. Stephenson, and Cadwallader C. Washburn.