The Plains of Chalmette by Jack Caldwell
It is 1814, and America’s second war against Great Britain is going badly. Now the enemy is ready for its knock-out punch. They seek to take New Orleans, and by doing so, control the Mississippi River and North America forever.
Major Matthew Darcy of Baltimore is dispatched to help defend the beleaguered city, and discovers an alien place that does not trust its new countrymen. He also finds forbidden love with a lovely Cajun-Creole lady.
Now, with a devastating invader at the city’s door, Darcy joins General Andrew Jackson’s rag-tag army of backwoodsmen, Creoles, free blacks, and buccaneers in the face of overwhelming odds.