As settlers moved westward, they often displaced Native American tribes from their traditional lands. This led to conflict between settlers and Native Americans, as well as the forced removal of Native Americans to reservations.
Environmental degradation
The westward movement also led to environmental degradation, as settlers cleared forests, mined for resources, and polluted rivers and streams. This damage to the environment had a negative impact on both Native Americans and settlers alike.
Conflict with Mexico
The westward movement eventually led to conflict with Mexico, which resulted in the Mexican-American War (1846-1848). The United States won this war and gained a significant amount of territory from Mexico, including the present-day states of California, Nevada, Utah, Arizona, and New Mexico.
Economic inequality
The westward movement also contributed to economic inequality, as many of the settlers who moved westward were poor and struggling to make a living. This led to the development of a frontier economy based on subsistence farming, ranching, and mining.
Disease
The westward movement also led to the spread of disease, as settlers brought new diseases with them that Native Americans were not immune to. This resulted in epidemics that decimated Native American populations.