The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975.
See Vietnam War
Seymour Skinner is a veteran of this war.
Seymour Skinner: POW
Unnamed Bartender: WIA (claims he got a metal [butt] in Vietnam)
Skinner's entire company: KIA
Skinner has several flashbacks of the Vietnam war.