What was the 19th century belief that the United States would inevitably expand westward to the Pacific Ocean called?

The belief that the United States would inevitably expand westward to the Pacific Ocean is known as Manifest Destiny. This ideology emerged in the 19th century and was rooted in the conviction that Americans were destined by God to spread democracy and civilization across the continent. Manifest Destiny was used to justify the expansion into territories that were inhabited by Native Americans and other nations, reflecting a potent mix of nationalism, territorial ambition, and a sense of divine destiny.

The concept had profound implications for American policy and conflict, driving actions such as the annexation of Texas, the Oregon Trail migration, and the Mexican-American War. It influenced public sentiment and political actions during this period, often leading to significant consequences for the people residing in the areas that were claimed by the United States. This belief was widely accepted in American culture and helped shape the nation’s identity during a transformative era in U.S. history.