Although the United States of America had gained separation from the British as a result of the Revolutionary War, Arkansas remained in Spanish hands after the conflict. Americans began moving west to Kentucky and Tennessee, and the United States wanted to guarantee these people that the Spanish possession of the Mississippi River would not disrupt commerce. Napoleon Bonaparte's conquest of Spain shortly after the American Revolution forced the Spanish to cede Louisiana, including Arkansas, to the French via the Third Treaty of San Ildefonso in 1800. England declared war on France in 1803, and Napoleon sold his land in the new world to the United States, today known as the Louisiana Purchase. The size of the country doubled with the purchase, and a stream of new White settlers led to a changed dynamic between Native Americans and Arkansans. Prior to the Louisiana Purchase, the relationship between the two groups was a "middle ground" of give and take. These relationships would deteriorate all across the frontier, including in Arkansas.