sentences:  Finally the U.S. wanted to curtail Britain's attempts to get access to the Mississippi, access implicit in the Treaty of Paris ending the American War of Independence, and which Britain sought into the nineteenth century.The United States' assertion of dominion over its new territories parried and reversed the British domination of the fur trade in the upper Mississippi valley, which had continued for decades after the Revolutionary War settlement which had assigned those territories to the new nation.Later, the economic dependence of the Selkirk Settlement and the Canadian northwest on the Red River trade routes to U.S. markets came to pose a threat to British and Canadian control of their territory.