“Manifest Destiny” is a term deeply embedded in the American historical lexicon, encapsulating a complex set of beliefs and attitudes that have influenced the nation’s expansionist policies and self-image. This ideology, which emerged prominently in the mid-19th century, posited that God had destined the white settlers of the United States to spread democracy and capitalism across North America. This belief in a divinely ordained mission not only justified territorial expansion but also framed it as a moral imperative, influencing American policy and identity.

The term itself is often said to be coined by journalist John L. O’Sullivan in 1845, in the context of advocating for the annexation of Texas and disputing British claims in the Oregon Territory. O’Sullivan argued that the United States had a manifest destiny from Providence to expand across the continent for the uninhibited growth and prosperity of the rapidly increasing population. This phrase quickly became a rallying cry for expansionists, encapsulating the intertwined ideas of American exceptionalism, the virtue of the American way of life, and a divine mandate for expansion.

Manifest Destiny was not just a theoretical construct but an ideological force that influenced real policy decisions and actions, leading to the annexation of territories such as Texas, Oregon, and, following the Mexican-American War (1846-1848), the regions that would become California, Nevada, Utah, Arizona, New Mexico, Colorado, and Wyoming.