Parade begins during the Civil War with a Confederate Soldier about to leave for battle and saying goodbye to his Lila. The action fast forwards fifty years and we see an older actor playing that same Confederate Soldier only fifty years older and missing his left leg (or is it his right?). Basically, one of the underlying themes of the show is that the South is still healing from the wounds of the Civil War.
The Life and Caroline or Change both have references to Vietnam. Caroline's oldest son is stationed in Vietnam and Queen's lover/pimp, Fleetwood is a Vietnam vet going through flashbacks and addicted to cocaine and they talk about how he hocked his Purple Heart and Fleet tells one guy, "I didn't see you in the jungle." So these shows aren't necessarily about war but war is certainly a theme.
Butters, go buy World of Warcraft, install it on your computer, and join the online sensation before we all murder you.
--Cartman: South Park
ATTENTION FANS: I will be played by James Barbour in the upcoming musical, "BroadwayWorld: The Musical."