June Tabor did an absolutely devastating version of "The Writing of Tipperary"/"It's a Long Road to Tipperary"
A tragicomic song written by the late Davy Steele: a young man enlists expecting an easy ride ("Don't show fear, don't volunteer"), not realizing WWI is in the offing:
The Battle of New Orleans is kind of a family song. I've sung it for as long as I can remember. It's probably the only song written about the War of 1812 other than The Star-Spangled Banner lol.
Johnny Horton has a lot of great war songs. Sink the Bismarck being another really good one.
WW2 paratroopers would sing this (a song about parachutes malfunctioning and dying a horrible death because of that) before and during actual paratrooper missions