Why Did Americans Move West in the 1800s?

Manifest Destiny
One principle that guided the country's westward expansion was Manifest Destiny, or the belief that the United States had a divinely given responsibility to settle and spread democracy across North America. Although the term didn't appear in print until 1845, the concept of Manifest Destiny had been alive and well in the United States since Jefferson's presidency. Supporters used this belief in defense of the decision to claim the Oregon Territory, annex Texas as well as the Treaty of Guadalupe Hidalgo, in which Mexico gave up its rights to what is now Arizona, New Mexico, California, Colorado, Nevada, Utah and Wyoming.

Expanded Opportunities
People agreed to move west for many different and highly personal reasons. For some of them, it gave them an opportunity to own their land, especially after Congress started passing the Homestead Acts in 1862. The first Homestead Act gave up to 160 acres of free land to any adult citizen who had a family, paid a registration fee and agreed to live on the property for five years. Others preferred the vast expanses of open space to the tight quarters of urban tenements. Another group, especially artisans turned west as industrialization in the cities left them without jobs that were still needed in the new territories. The discovery of gold in California attracted speculators who sometimes sold their property to pay for the journey to San Francisco. This Gold Rush of 1849 spiked California's population and encouraged the development of infrastructure in the gold mining towns.

The Question of Slavery
The issue of slavery also played a role in the United States' expansion. For as long as possible, the federal government worked to maintain a balance between the representation of pro-slavery and anti-slavery states in the union. Each time the country acquired new territory, the debate centered on whether or not it would lead to the addition of a new free or slave state. The Missouri Compromise of 1820 let Maine enter the Union as a free state and Missouri in as slave state, establishing the precedent of keeping an equally balanced number of each type of state. It also prohibited slavery in any land in the new territory that lies north of Missouri's southern border. Thirty-four years later, the Kansas-Nebraska Act allowed the settlers in new territories the right to decide whether to allow slavery or outlaw it. This led to an influx of people in the Kansas and Nebraska territories, as people moved there just so they could vote on the slavery issue.