John L. O'Sullivan

John L. O'Sullivan was a 19th-century American journalist and editor known for coining the term "Manifest Destiny" in 1845. This phrase expressed the belief that the United States was destined to expand across North America. O'Sullivan used the term to justify westward territorial growth, emphasizing a perceived divine right for Americans to spread their civilization. His ideas influenced U.S. policies and public opinion during a period of rapid territorial expansion, shaping the country’s approach to westward expansion and reflecting prevailing attitudes of the time.