"The Last Reunion" is a short story written by Harry Turtledove. It was first published in Amazing Science Fiction Magazine in June 1992, and reprinted in the Turtledove collection Departures in 1993.
It is a fictionalized account of the 1932 reunion of Confederate veterans of the American Civil War in Richmond, Virginia, attended by John Houston Thorpe, former captain of Company A of the 47th North Carolina. Thorpe spends a few nights talking and interacting with his fellow veterans, remembering the good and the bad of warfare. One night, after a joyous celebration and dancing, Thorpe dies in his sleep, and discovers that the men who died in battle during the Civil War go to a kind of Valhalla, where they still fight, although in a far more congenial way.