Image Credit: Wikimedia Commons
Pictured Left to Right: John Gibbon, George Armstrong Custer, Cyrus B. Comstock, Orville E. Babcock, Charles Marshall, Walter H. Taylor, Robert E. Lee, Philip Sheridan, Ulysses S. Grant, John Aaron Rawlins, Charles Griffin, unidentified, George Meade, Ely S. Parker, James W. Forsyth, Wesley Merritt, Theodore Shelton Bowers, Edward Ord. The man not identified in the picture’s legend is thought to be General Joshua Chamberlain, a hero of Gettysburg who presided over the formal surrender of arms by Lee’s Army of Northern Virginia on April 12, 1865.
https://en.wikipedia.org/wiki/Battle_of_Appomattox_Court_House