Nathan A. Farwell, U.S. Senator from Maine Thomas W. Ferry, U.S. Representative and U.S. Senator from Michigan Horace Greeley, publisher and U.S. Representative from New York William S. Groesbeck, state legislator from Ohio Andrew Jackson Hamilton, U.S. Representative from Texas Aaron Harding, U.S. Representative from Kentucky James K. Holland, state legislator from Texas Samuel Hooper, U.S. Representative from Massachusetts George S. Houston, U.S. Representative from Alabama Reverdy Johnson, U.S. Senator from Maryland James Harlan, U.S. Senator from Iowa Jacob Merritt Howard, U.S. Senator from Michigan William Lawrence, U.S. Representative from Ohio John Wesley Longyear, U.S. Representative from Michigan John L.N. Stratton, U.S. Representative from New Jersey Samuel S. Marshall, U.S. Representative from Illinois Horace Maynard, U.S. Representative from Tennessee Robert Mallory, U.S. Representative from Kentucky Thomas Amos Rogers Nelson, U.S. Representative from Tennessee Richard Oglesby, Governor of Illinois James Lawrence Orr, Governor of South Carolina Halbert E. Paine, U.S. Representative from Wisconsin George Hunt Pendleton, U.S. Senator from Ohio Cyrus L. Pershing, jurist and later candidate for Governor of Pennsylvania Thomas G. Pratt, Governor and U.S. Senator from Maryland Henry Jarvis Raymond, U.S. Representative from New York James S. Rollins, U.S. Representative from Missouri Robert Cumming Schenck, U.S. Representative from Ohio James Speed, U.S. Attorney General John Dodson Stiles, U.S. Representative from Pennsylvania Byron Gray Stout, U.S. Representative from Michigan William Barrett Washburn, U.S. Representative from Massachusetts Peter Godwin Van Winkle, U.S. Senator from West Virginia Fernando Wood, copperhead Mayor of New York City Clement Vallandigham, copperhead from Ohio. He was elected to the convention but withdrew to avoid disturbing the harmony of the convention. Further reading McKitrick, Eric. Andrew Johnson and Reconstruction (1960) pp 394–420 Thomas Wagstaff. "The Arm-in-Arm Convention," Civil War History 1968 14(2): 101-119 The proceedings of the National union convention, held at Philadelphia, August 14, 1866 at Internet Archive. primary sources See also National Union Party (United States) 1864 National Union National Convention References External links Address to President, by Hon. Reverdy Johnson, Aug. 18, 1866, communicating proceedings National Union Convention entered into the record of Johnson's impeachment trial. Cartoon mocking the convention by Thomas Nast, originally published in Harper's Weekly, September 29, 1866 Reconstruction Era 1866 in American politics 1866 in Pennsylvania Political conventions in Philadelphia 1866 conferences August 1866 events