Homestead Act: The Homestead Act was a law that granted free land to settlers willing to develop it. (e.g., farming) This encouraged further western settlement.
Transcontinental Railroad: The Transcontinental Railroad was a railway system that connected the East and West coasts of America, making transportation faster and easier for settlers moving westward.
Manifest Destiny: Manifest Destiny was an idea popular during this time period that claimed it was America's destiny to expand its territory from coast to coast.