In the 1783 Treaty of Paris following the American Revolutionary War, the British Crown ceded all its territories south of the Great Lakes to the United States (US). As the treaty made no mention of England's Native American allies, the US had to negotiate separate peace agreements with each of the nations. The important issues to be settled included not only peace, but also the ownership of vast tracts of land which the United States considered to be under its control by the British cession. By 1789, US officials realized that, in the words of Secretary of War Henry Knox, "the Indians are especially tenacious of their lands, and generally do not relinquish their right, excepting on the principle of a specific consideration, expressly given for the purchase of the same." After the United States and the Seven Nations signed a treaty in 1797, its legitimacy was challenged by other Native Americans on the grounds that the signatories were unauthorized to cede land.