The message of this song was to discourage men going to war which responds to the Kandyan Wars, in short it's an anti-war song. Meanwhile the song, "When Johnny Comes Marching Home", which was used during the American Civil War, expressed people longing for the return of their friends and relatives who are fighting in the civil war.
The lyrics of the song "Johnny I Hardly Knew Ye" was written by Joseph B. Geoghegan and was published in London on 1867, meanwhile the song "Johnny Comes Marching Home" was composed by an Irish-American bandleader Patrick Gilmore, the song was published on 1863.
For an anti-war song, the sound was very electrifying that it can make you sign up for the military and go to war.
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Tsutayawhat are you singing ?I'm home. Thank you for watching the houseI rented Black Lagoon OVASeriously!?A popular traditional song from Ireland in the year 1796~1818. It's a war ballad and marching song.
The song took place during the Kandyan wars in British occupied Ceylon.
Later, in 1845~1849, many Irish moved to America to escape famine, and they brought the song with them.
During the civil war period, the song became "Johnny Came Marching Home".
The song is used for the ending of Black Lagoon OVA and also popularized in Die Hard 3.
There's study that says "Johnny Came Marching Home" is actually not a rewrite of this song (ref: Wikipedia).
TN: can't read some sentences. Please check