Irish-American bandleader Patrick Gilmore wrote the lyrics to "When Johnny Comes Marching Home" during the American Civil War.

Its first publication was deposited in the Library of Congress on September 26, 1863, with words and music credited to "Louis Lambert"; copyright was retained by the publisher, Henry Tolman & Co., of Boston.

[2] Gilmore is said to have written the song for his sister Annie as she prayed for the safe return of her fiancé, Union Light Artillery Captain John O'Rourke, from the Civil War,[3][4][5] although it is not clear if they were already engaged in 1863; the two were not married until 1875.

"[7] The melody was previously published around July 1, 1863, as the music to the Civil War drinking song "Johnny Fill Up the Bowl".

[14] It became a hit in England and Ireland as well and was eventually lyrically rewritten and became the related tune "Johnny I Hardly Knew Ye".

The men will cheer, the boys will shout, The ladies, they will all turn out, And we'll all feel gay, When Johnny comes marching home.

The laurel wreath is ready now, To place upon his loyal brow, And we'll all feel gay, When Johnny comes marching home.

And let each one perform some part, To fill with joy the warrior's heart, And we'll all feel gay, When Johnny comes marching home.

[citation needed] In the John Ford western The Horse Soldiers, the last line was changed to "And we'll all raise hell when Johnny comes marching home".

British punk band The Clash recorded a reworded version in 1978 titled "English Civil War (Johnny Comes Marching Home)".