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What if the Adams-Onis Treaty was more extensive?

By Steve Payne

This article was originally posted on Today in Alternate History (twitter)and the original article can be found there. Please check that blog for more like this.

Map showing the results of the OTL treaty made by wikimedia user 'Citynoise' and shared under the Creative Commons Attribution-Share Alike 2.5 Generic license.

After the end of the American War of Independence, one of the big winners was Spain. They had regained East and West Florida from the British, maintained controlled over Louisiana which they had bought from France and through New Spain owned much of the modern South West USA including California and Texas. On paper, Spain was the dominant force in North America, owning the vast majority of modern USA as well as all of Mexico, most of Central America, the Dominican Republic and Cuba. In reality however Spanish control was largely nominal in a lot of their territory, with only a thin layer of government control and a lot of the land unexploited with native peoples largely actually governing the area. Louisiana meant in reality New Orleans and even that tried to rebel and rejoin France. And the Floridas were a land mostly populated by Native Americans, criminals, escaped slaves and political exiles and the land became a lawless anarchy.

Without the Napoleonic Wars it is possible for Spain to recover but the Peninsular War with the French ended any hope of that. For long centuries the two Catholic powers had fought each other and occasionally allied together against Protestant adversaries. But this confrontation was very different, one of the many costs of the Napoleonic Wars was to end both country's aspirations in the Western Hemisphere. Louisiana was reclaimed by France and then, after the Haitian Revolution ended Napoleon's ambitions in the Western Hemisphere, sold to the USA. And that neglect would lead to the Mexican War of Independence beginning in 1810. By 1814, the once-mighty Spanish Empire was exhausted and broken and the vultures were circling.

West Florida was lost to an American backed rebellion in 1810, creating the unrecognised Republic of West Florida which was annexed to the USA in 1812, the Spanish supporting population of the Tangipahoa and Tchefuncte River regions were crushed by the Louisianian Milita and forced to flee into East Florida. In 1812 the USA attempted the same trick in East Florida but were forced to withdraw in disgrace lest they start a war with Spain while fighting the British at the same time.

That war, the War of 1812, was started due to annoyance over continued British interference in their affairs, in particular the press ganging of Americans into the Royal Navy. The aspiration of the nascent United States was to create a distinctly separate sphere of influence, considering intervention in the political affairs of the Americas by foreign powers a potentially hostile act. Despite the distraction of British leadership in the Peninsular War, Washington would be frustrated in achieving this objective, suffering the ultimate national indignity of having their Executive Mansion utterly destroyed by Redcoats. But neither side could win, and the War of 1812 was fought to a negotiated conclusion.

Unable to capture British Canada, Washington set its sights to the south. This brought the hero of the Battle of New Orleans Andrew Jackson to Florida, where the USA annexed the Republic of West Florida and where the US army fought a one-sided struggle that exposed the utter weakness of the Spanish military situation as British backed natives and escaped Slaves would lead the fighting against the US rather than the Spanish there, something that continued after the British had made a peace with the USA in 1815. From 1816 to 1819, Jackson and his army would attack these natives and ex slaves despite the fact that they were in nominally Spanish territory, destroying 'Negro Fort' in 1816 and fighting the first Seminole War from 1817 onward.

With both the USA proving Spanish weakness in the region and an increasing number of rebellions starting elsewhere in the Spanish Empire, the politicians in Madrid accepted the need to disengage, withdrawing from their smaller and less populated colonies to both hold onto to their larger ones and to rebuild their shattered home country.

Secretary of State John Quincy Adams led negotiations with the Spanish minister plenipotentiary Luis de Onís y González-Vara on behalf of President James Monroe and King Ferdinand VII. With France crushed, and Great Britain's aggression still in recent memory, the United States welcomed a new partner, offering favourable commercial terms that would bring long-term economic benefits to Spain. In exchange, in 1819 the Adams-Onís Treaty was signed wherein the the United States gained Florida and a border between the USA and the rebelling New Mexico was agreed.

But what if that treaty went a bit further and the USA also purchased Cuba and Puerto Rico too? The below scenario is one take on a weaker Spanish position meaning they gave up more land.


The Adams-Onís Treaty would have unpredicted consequences for the United States. Florida gained Statehood in 1845, but due to their ethnic diversity, Cuba and Puerto Rico remained American overseas territories. The prospect of making vast profits from tobacco and sugar encouraged southerners to purchase plantations in Cuba. Under the brilliant leadership of Colonel Ambrosio José Gonzales, it would be these southerner's heirs that seized power of the island in 1861 and declared a Confederate State of Cuba, opening up another front of the American Civil War.



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