Manifest Destiny was a 19th-century idea that originated in the United States and was based on the belief that it was the country's divine mission to expand its territory and spread its influence throughout the continent of North America. The term "manifest destiny" was first used in 1845 by a journalist named John O'Sullivan, who argued that it was America's destiny to spread its democracy and values westward. This idea gained traction during the 1840s and 1850s, as the United States acquired new territories through diplomacy and military conquest, including Texas, California, and the Southwest. The idea of manifest destiny was used to justify westward expansion and the displacement and subjugation of Native American populations. While it was a powerful motivator for many Americans, it also led to conflict and violence and remains a controversial and contested idea in American history.