OCOURX_081009_041
Existing comment: The Transfer of Upper Louisiana to the United States at St. Louis, March 9-10, 1804:

The United States acquired the Territory of Louisiana from the French in May 1803. Although France had re-acquired the territory from Spain as a result of a secret treaty in 1800, Spain was still administering Upper Louisiana when the Louisiana Purchase occurred. The Louisiana Territory was passed from Spain to France, and then to the United States in a unique ceremony held in St. Louis on March 9-10, 1804.

Captain Charles De Hault Delassus, the Spanish Commandant at St. Louis, ordered the transfer ceremonies to take place in front of the Government House. French authorities in New Orleans deputized an American, Captain Amos Stoddard, to accept the territory from Spain on behalf of the French Republic. The French flag was raised on March 9.

On March 10, Captain Stoddard conveyed the territory from France to the United States, represented by Meriwether Lewis, and the United States flag was raised. That ceremony formally opened the vast lands of the Trans-Mississippi west to United States expansion.
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