Final answer:
People moved past the Appalachian Mountains due to Manifest Destiny, economic opportunities like the California Gold Rush, government incentives like the Homestead Act, improved transportation infrastructure, and the completion of the Transcontinental Railroad.
Step-by-step explanation:
The movement of people past the Appalachian Mountains was significantly influenced by the ideology of Manifest Destiny, the California Gold Rush of 1849, and the completion of the Transcontinental Railroad in 1869. The federal government played an essential role by encouraging westward migration through land incentives such as the Homestead Act of 1862, which offered 160 acres of free land to households willing to move west. Improvements in transportation, including roads, canals, and railroads, funded by the federal government and states, further facilitated this migratory push.
Westward expansion was not just fueled by economic opportunity but also by a myriad of motivations including the desire to spread American values and to prosper from agricultural and mining endeavors. This westward movement resulted in significant demographic shifts and cultural clashes as settlers encountered Native American tribes and other residents of the 'middle ground.'
Ultimately, the westward migration was a complex affair, driven by a combination of government incentives, economic necessity, and the belief in America's destiny to expand its territories. This period of American history represents not only a geopolitical expansion but also the transformation of the American identity.