In what way did the 1842 expedition of John C Fremont contribute to the westward migration?

John C. Frémont's 1842 expedition played a crucial role in westward migration by mapping uncharted territories and providing detailed accounts of the landscapes, resources, and potential routes to the West. His reports and the accompanying maps inspired many settlers by highlighting the opportunities for agriculture and settlement in California and Oregon. Additionally, Frémont's promotion of the idea of Manifest Destiny and the potential for expansion further fueled the migration of thousands seeking new beginnings in the West.