David Rovics singing “Saint Patrick’s Battalion,” a song celebrating the Irish who deserted and fought alongside the Mexican army against the United States during the Mexican American War, 1846-1848.
Want to learn more?
- Batallón de San Patricio: the Irish Heroes of Mexico by Martín Paredes
- Saint Patrick’s Battalion from Wikipedia
- One Man’s Hero feature film directed by Lance Hool and starring Tom Berenger
h/t Dave W.
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View From Casita Colibrí 
Informative post. Have seen “One Man’s Hero twice” and visited the plaque in San Angel Mexico City devoted to this brave battalion