The Struggle for Western Territory (1825-1890). After Congress passed the Northwest Ordinance in 1787, pioneers began to cross the Allegheny Mountains into the territory north of the Ohio River. More settlers moved westward in the early 1800s, after the explorations of Zebulon Pike and John C. Fremont. Going West meant land, trapping and trading, and gold—in short, economic opportunity! Within a few years after the War of 1812, Americans used the resources of the continent to create one of the world's richest countries and expand the Nation's boundaries from the Atlantic to the Pacific Ocean.

The incredible 19th century search for a better way of life was driven by improvements in transportation and communication--and our superior weaponry. We invented the steam engine and power-driven machines, such as reapers. We opened the Erie Canal, developed a large network of post roads, and invented the electric telegraph. The railroads had a major impact on the old, slower ways of life. By 1869, the last spike had been driven on the central line to the Pacific and travel from coast to coast was possible in days instead of weeks.

During this time--led by a series of expansionist Presidents--the United States fought a war with Mexico from 1845 to 1848, annexed Texas and California, and settled the Oregon territory. Native Americans were pushed aside and eventually settled onto reservations to make way for the new states.