USA HISTORY

Detailed explanation-1: -Expansion of the United States moved steadily westward from the late 18th to the mid 19th centuries. This territorial movement displaced most of the Native American peoples who lived in those lands for thousands of years before the arrival of European colonists.

Detailed explanation-2: -However, westward expansion provided the United States with vast natural resources and ports along the Atlantic, Pacific and Gulf coasts for expanding trade, key elements in creating the superpower America is today.

Detailed explanation-3: -The Homestead Act, passed in 1862, allowed settlers to claim 160 acres of land for free. Another important factor was completion of the first transcontinental railroad in 1869; the railroad led to much more rapid western migration and also facilitated economic development.

Detailed explanation-4: -Propounded during the second half of the 19th century, the concept of Manifest Destiny held that it was the divinely ordained right of the United States to expand its borders to the Pacific Ocean and beyond.