Robert E. Lee and his officers signed paroles printed by the Union Army for the surrender of the Army of Northern Virginia
Source: National Archives, American Originals: Civil War and Reconstruction (1850-1877)
defeated Confederate soldiers were paroled at Appomattox, after which they walked home (and caught trains wherever possible)
Source: National Park Service, The Appomattox Campaign
the well-supplied Union Army had printing presses in its wagon train, and they were used to produce paroles at Appomattox
Samuel Grymes signed the amnesty oath in August 1865
Source: National Archives, Records related to Samuel A Grymes
Source: FilsonHistoricalKY, Ends of War: The Unfinished Fight of Lee's Army After Appomattox - Caroline E. Janney