Final answer:
The change in westward migration that occurred in 1848 was the California Gold Rush, which attracted thousands of people to the West Coast in search of gold.
Step-by-step explanation:
One change in westward migration that occurred in 1848 was the California Gold Rush. The discovery of gold in California in 1848 attracted thousands of people to the West Coast in search of quick riches. This led to a mass exodus of settlers from different parts of the United States and even from other countries. People from various backgrounds, including Americans, Europeans, and Chinese, traveled to California to join the gold rush and seek their fortune.
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