Final answer:
The event known as the Gold Rush brought people west by the tens of thousands in California.
Step-by-step explanation:
The event that brought people west by the tens of thousands in California was known as the Gold Rush. It took place in the mid-19th century when gold was discovered at Sutter's Mill in 1848. The news of gold being found spread rapidly, attracting prospectors from all over the country and even from around the world.
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