Irving Katz, "Belmont, August," American National Biography Online, February 2000, http://www.anb.org/articles/04/04-00092.html.
Following his nomination in 1860 by the northern wing of the Democratic party, Douglas selected Belmont to run the presidential campaign as chairman of the Democratic National Committee. Following Douglas's defeat in November and his death the following June, no political heir appeared; most of the veteran Democrats in Congress were southerners who had seceded with their states. Belmont then assumed the party's national leadership in his position as chief executive officer of the existing organization and held it for twelve years. Few northern Democrats challenged him, owing to the distractions of war and the ensuing reconstruction. Belmont sided with "War" Democrats and used his influence as an international banker to discourage the Rothschilds and other prominent European financiers from investing in or underwriting Confederate bonds. In 1862 Belmont, with Samuel J. Tilden and other leading Democrats, purchased the New York World and installed as editor Manton M. Marble, one of Belmont's closest, lifelong friends. Until Marble's retirement in 1876, he and Belmont succeeded in making the World the nation's leading Democratic organ. In 1864 Belmont helped an ally, General George B. McClellan (1826-1885), obtain the party's presidential nomination, but Abraham Lincoln easily won reelection. Belmont fought against any Democratic merger with President Andrew Johnson's National Union party in 1866. When his first choice for the 1868 nomination, Chief Justice Salmon P. Chase, refused to desert the cause of African-American suffrage, Belmont saw the prize go to former New York governor Horatio Seymour (1810-1886), who, as Belmont predicted, campaigned weakly and lost to General Ulysses S. Grant. Belmont resigned as Democratic national chairman after the 1872 national convention and gradually reduced his political activities, though he championed Delaware senator Thomas F. Bayard's presidential ambitions in the next three campaigns.