22 Feb Today in History: Adams-Onís Treaty of 1819
One hundred eighty-eight years ago today, on February 22, 1819, the United States and Spain signed the Adams-Onís Treaty (also known as the Florida Purchase Treaty or the Transcontinental Treaty of 1819) by which the United States acquired Florida from Spain and the two countries settled their boundary dispute regarding the western territories. Thanks to the treaty we became a nation from sea to shining sea.
The relevant provision of the treaty ceding Florida to the United States states that:
His Catholic Majesty cedes to the United States, in full property and sovereignty, all the territories which belong to him, situated to the eastward of the Mississippi, known by the name of East and West Florida. The adjacent islands dependent on said provinces, all public lots and squares, vacant lands, public edifices, fortifications, barracks, and other buildings, which are not private property, archives and documents, which relate directly to the property and sovereignty of said provinces, are included in this article.
Regarding the boundary dispute, as discussed here, the treaty settled the dispute by drawing clear borders, roughly granting Florida and Louisiana to the United States while giving to Spain everything west of Louisiana from Texas to California.
I love the provision at the end of Article III of the Adams-Onís Treaty in which the Unites States “renounces forever” any and all claims to territories west and south of the border, i.e., California, Arizona, New Mexico, Texas, Utah, Nevada and much of Colorado. Here is the provision:
The two high contracting parties agree to cede and renounce all their rights, claims, and pretensions to the territories described by the said line, that is to say: The United States hereby cede to His Catholic Majesty, and renounce forever, all their rights, claims, and pretensions, to the territories lying west and south of the above-described line; and, in like manner, His Catholic Majesty cedes to the said United States all his rights, claims, and pretensions to any territories east and north of the said line, and for himself, his heirs, and successors, renounces all claim to the said territories forever.
Not so trivial footnote:
Foster v. Neilson, 27 U.S. 253 (1829), overruled on other grounds United States v. Percheman, 32 U.S. 51 (1833), which established the doctrine on self-executing treaties, was concerned with the status of Spanish land-grants under this treay.
That is interesting, but I’d like to respond to your implicit point about America’s failure to maintain its renunciation of claims over the southwest and west: Remember that Texas won its independence from Mexico in 1836 and was a sovereign country when it asked the US to admit it as a state in 1845.