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United States Expansion after the Treaty of Paris in 1783

A map illustrating the expansion of the United States of America following the Treaty of Paris (September 3, 1783), which ended the War of the American Revolution, recognized U.S. independence, and granted it sizeable additional territory. Following the 828,000 square miles (about 2 million square kilometers) “Louisiana Purchase” from Napoleonic France in 1803, the United States doubled in size, and its Westward Expansion began in earnest. In less than half a century, the western border shifted from the Mississippi River to the Pacific Ocean through territories gained from Spain and then Mexico, agreements with Great Britain, and the annexation of Texas.