THE LOUISIANA PURCHASE
France turned over New Orleans, the historic colonial capital, on December 20, 1803, at the Cabildo, with a flag-raising ceremony in the Plaza de Armas, now Jackson Square. Just three weeks earlier, on November 30, 1803, Spanish officials had formally conveyed the colonial lands and their administration to France. Spain ceded Louisiana back to France under the secret Third Treaty of San Ildefonso https://en.wikipedia.org/wiki/Third_Treaty_of_San_Ildefonso …