Manifest Destiny was the belief that The United States colonists had a right and were destined to settle all of North America, and that it was gods plan (divine right) that they take the land as their own.
This created a mad rush towards the west and new lands. This was seen as a fresh start for many Americans and the newest way to get rich. Though this land was already occupied by Native Americans, it did not slow down settlers pushing the Natives further and further west.
Indian Revmoal Act 1830
One of the largest factors that played in Manifest
Destiny was the Indian Removal Act of 1830, set in place by President Andrew Jackson. This act allowed Jackson to promise lands west of The Mississippi to Native Tribes that agreed to give up their lands and move west.
The Map above shows the paths taken by "removed" Indian Tribes, it shows where they originally were settled and where The US government placed them into reservations. These paths westward would later be named The Trail of Tears.