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Louisiana Purchase Treaty (1803)


The Louisiana Purchase Treaty (April 30, 1803) provided for the cession of the French province of Louisiana to the United States for approximately $11,250,000. France had reacquired Louisiana from Spain as part of Napoleon's plan to reestablish a French empire in the New World. The United States had tolerated weak Spanish control at the mouth of the Mississippi, especially since the Pinckney Treaty of 1795 gave Americans the right to navigate the river and use the port of New Orleans; but Louisiana in the hands of Napoleonic France threatened the security, commerce, and growth of the country. President thomas jefferson sought a diplomatic resolution, hoping to obtain from France at least the continuation of Spanish guarantees and, at best, the cession of New Orleans together with the Floridas, if France possessed them. In a surprising about-face, however, Napoleon renounced the whole of Louisiana.

The acquisition of Louisiana—some 828,000 square miles, virtually doubling the land area of the United States—challenged the government in several ways. First, the boundaries were obscure. Was Texas included? Or West Florida? Jefferson made pretensions to both. Article III of the treaty said that the inhabitants should be incorporated in the Union and enjoy all the rights of citizens of the United States. Unfortunately, the Constitution Jefferson and his party were pledged to construe strictly made no provision for acquiring foreign territory, much less admitting that territory and its people into the Union. The treaty, Jefferson declared, was "an act beyond the Constitution" and ought to be sanctioned retroactively by amendment. He drafted a 375-word amendment. When congressmen objected that Louisiana might be lost because of constitutional scruples, Jefferson acquiesced in silent expansion of the treaty power even as he reiterated his belief that it made the Constitution "a blank paper by construction." (The Supreme Court, in american insurance company v. canter, 1828, later upheld the authority to acquire and govern territory under the treaty and war powers.) The Senate ratified the treaty on October 20, 1803. Two months later the American flag was raised at New Orleans.

Government of the territory also raised constitutional difficulties. The Enabling Act, in October, vested the President and his agents with full powers, civil and military. Querulous Federalists said it made Jefferson "as despotic as the Grand Turk." The Louisiana Government Act six months later created the Orleans Territory in populous lower Louisiana, extended to it many federal laws, and vested authority in a strong governor and weak legislative council, both appointed by the President. In the view of the President and Congress the rights of self-government, for which Creole Louisianans were unprepared, should be introduced gradually as the territory became "Americanized" in its population, habits, and institutions. The Louisianans demanded immediate statehood. Although this was denied, Congress in March 1805 introduced the second stage of territorial government, including a representative assembly, more or less on the plan of the northwest ordinance. Five years later the statehood commitment of the treaty was met. The American theory of an expanding union of equal self-governing states thus survived its severest test.

Merrill D. Perterson

(see also: Theories of the Union.)


Brown, Everett S. 1920 The Constitutional History of the Louisiana Purchase, 1803–1812. Berkeley: University of California Press.

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