Answer:
The westward expansion and movement after the Civil War had several major impacts on the nation:
1. Economic growth and development: The settlement of the western frontier led to the development of new industries, agriculture, and resource extraction that boosted the national economy. Railroads were built to connect the West to the rest of the country, facilitating trade and commerce.
2. Population growth: The West saw a large influx of settlers, drawn by the promise of land, opportunity, and a new start. This helped grow the overall U.S. population. Many new communities and cities sprung up across the West.
3. Shifting of population center: As more people moved West, the geographic center of U.S. population shifted from the Eastern Seaboard states toward the Midwest. This changed the balance of political power in the country.
4. Transformation of the environment: The growth of mining, logging, ranching, and farming in the West transformed the natural environment on a massive scale. Native lands and wildlife habitats were dramatically altered.
5. Rise of new political issues: Issues arose from the western expansion like disputes over land grants, property rights, Native American policies, farming, railroad regulation, and natural resource use that occupied and divided politicians and the public.
6. Cultural diversification: The western migration was composed of a diverse mix of people from different backgrounds, ethnicities, and nations, which helped make the nation's culture more varied and heterogeneous.
In many ways, the post-Civil War western expansion solidified America's identity as a nation defined by westward movement, continual growth, and the promise of new frontiers and opportunities.