The Army of the Potomac
Chamberlain was nominated the orator for the first annual reunion of the Army of the Potomac.
This honor may be due in part to Chamberlain's fellow officers knowledge of his occupation before the war as professor of Oratory at Bowdoin College.
When he speaks on page 83 hoping "tardy justice" "may be done to officers whose character and services in behalf of the Republic deserve something better than its hasty rebuke."
He is most likely referring to General Warren who was taken from command of the 5th corps at the battle of Five Forks.
It would not be for another ten years before Warren would finally get a court of inquiry to look into his case.
For a newspaper clipping about the event see Newspaper Clippings of Speeches