U.S. Senate ratifies Mandan treaty

Background. The Mandan are a Native American tribe of the Great Plains, primarily living in what is now North Dakota. They were a trading nation, exchanging corn surpluses for bison meat. In 1825, they signed a peace treaty with the leaders of the Atkinson-O'Fallon Expedition, which established terms for their relationship with the United States.

Treaty Terms. The treaty required the Mandans to recognize the supremacy of the United States, admit that they reside on United States territory, and relinquish all control and regulation of trade to the United States. These terms defined the legal framework for the Mandan-U.S. relationship following the signing.

Ratification. The supplied passages do not provide evidence for the specific date or location of the U.S. Senate's ratification of the treaty. The legacy data suggests a ratification on 30 July 1825 at the United States Capitol, but this is not supported by the retrieved text.