The three effects of westward expansion in the United States during the mid-nineteenth century were Options B, C, and D that are:
- The Mormon religion's survival and development.
- Californians are working to create a diversified society.
- American Indian territories are being invaded by Christian missionaries.
The Other Options are incorrect as:
- Option A is incorrect as there were no immigrants from Mexico.
- Option E is incorrect as there was no Gadsden Purchase of land in the Southwest.
During the mid-nineteenth century, the United States began to expand westward:
- The quest for control of the West led to the annexation of Texas and the Mexican–American War in the mid-nineteenth century.
- Efforts to wrest western lands from native peoples and expand the republic by fighting Mexico were a huge success; few nations had ever grown so swiftly.
- This expansion sparked arguments about the fate of slavery in the West, escalating tensions between the North and South, and eventually leading to the collapse of American democracy and horrific civil war.
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