Exploration and Settlement
Who were the expansionists?
Not long after the colonies won the American Revolution (1775–83), founding the United States of America, a nationalistic (superpatriotic) spirit emerged in the hearts of many citizens of the new country. Eager to spread American ideals, many looked westward, northward, and southward to expand the territory of the Union beyond the original 13 states. These people were called expansionists. Not only did they favor the settlement of the frontier, but some advocated seizure of the southwest (from Spain and later from Mexico), Florida (from Spain), the Louisiana Territory (from France), and the Northwest Territories and even Canada (from Britain). By the 1840s the doctrine of Manifest Destiny—stating that the United States had a God-given right and duty to expand its territory and influence throughout North America—took hold.
The fires of expansionism were fanned by population growth during the 1800s. Pioneer settlement of the Plains and the Old Northwest (the present-day states of Ohio, Michigan, Indiana, Illinois, Wisconsin, and part of Minnesota) resulted in an increase in farmland and overall crop production; Yankee ingenuity resulted in inventions such as the cotton gin (1793) and the McCormick reaper (1831), which improved the processing and harvesting of raw materials such as cotton and grain; and a continuous influx of immigrants from Europe supplied labor for the factories that had popped up across New England and the mid-Atlantic states. All these factors combined to create a rapid population growth. In the two decades between 1840 and 1860 alone, the population of the United States more than doubled, increasing from just over 17 million to more than 38 million. Though the eastern seaboard cities grew, a system of new canals, steamboats, roads, and railroads opened up the interior to increased settlement. By 1850 almost half the population lived outside the original 13 states.
Though Canada, of course, remained in the hands of the British, the spirit of expansionism resulted in the United States’ relatively speedy acquisition of North American territories that had belonged to Spain, Mexico, France, and the British: By 1853 the United States owned all the territory of the present-day contiguous states, and by the end of the century, it owned all the territory of its present-day states—including Alaska (purchased from Russia in 1867) and Hawaii (annexed in 1898).