Which 1845 magazine first printed O'Sullivan's phrase 'manifest destiny'?

The 1845 magazine that first printed John O’Sullivan’s phrase “manifest destiny” was the United States Magazine and Democratic Review.

O’Sullivan was the magazine’s co-founder and editor, and he used the phrase in his July–August 1845 essay “Annexation.” He argued that the United States had a providential mission to spread across the continent, especially through the annexation of Texas. The expression initially attracted little public attention.

The phrase became much more influential after O’Sullivan used it again later in 1845 while defending U.S. claims to the Oregon Country in the New York Morning News. That second use helped turn the words into a rallying slogan for expansionists. The magazine itself, often called the Democratic Review, was a major voice of Jacksonian Democracy and also published important literary figures including Nathaniel Hawthorne and Walt Whitman.

A common mix-up is confusing the Democratic Review with the North American Review, a rival and generally more conservative publication. “Manifest destiny” described a powerful expansionist belief, not a formal government policy, and many Whigs, abolitionists, and Indigenous advocates criticized its territorial and racial assumptions.