In the mid-1700s when French-speaking settlers of Acadia entered the area they immediately observed red cypress trees stripped of their bark and decorated with skulls of birds and animals. They later found out that this line of trees marked the boundaries of tribal hunting grounds between two Indian tribes. The red Cypress trees reminded the French of red sticks which translates to Baton Rouge in French.
Due in large part to their continuing struggles with Britain; Spain became a clandestine ally of the American Colonies during the early part of the Revolutionary War, supplying the revolutionaries with gun powder and other military supplies for a price. The Spanish began smuggling arms and ammunition from the port of New Orleans—by the Roderigue Hortalez and Company trading company and up the Mississippi river, as well as Spanish warehouses in Havana, the Spanish port city of Bilbao and through the Gardoqui family trading company.
As the war progressed the Spanish became more active in their support of the Patriots by capturing the city of Baton Rouge from the British who had taken it from the Acadians.
The capture of Baton Rouge opened up—for the transport of military supplies—the Mississippi river from the port of Baton Rouge to the Gulf of Mexico and all points in-between. This was a great strategic victory for the Colonies.
The Spanish never formally declared their alliance with the Colonies because to do so would precipitate war from Britain before the Spanish were ready to go to war with the King.