In the annals of military pointlessness, few battles are quite as ridiculous as the Battle of New Orleans. It was fought 16 days after the official end of the War of 1812, of which it was a part, due to the fact that the peace treaty was signed in Europe, and the news took two months to reach America.
The Battle of New Orleans was important to later American history, though. It ended the war with a decisive American victory (in a war where neither side had managed to seize the advantage over the other), and it brought to prominence a commander named Andrew Jackson, who would later become the seventh President of the USA.
By Painting by Jean Hyacinthe de Laclotte (1766 – 1829), a member of the Louisiana Militia who participated in the battle; painted by him after the victory based on his sketches made at the scene. – New Orleans Museum of Art, Public Domain, Link
As mentioned in:
I Ain’t Marching Anymore — Phil Ochs
Lydia the Tattooed Lady — Groucho Marx
The Battle of New Orleans — Johnny Horton