formulated in 1823, promised that the U.S. would stay out of European affairs but would oppose European attempts to colonize the Americas.
a unilateral declaration by US President Monroe in 1823 that all of North and South America lay within the exclusive power of the United States.
an American foreign policy opposing interference in the Western hemisphere from outside powers
At the suggestion of Secretary of State John Quincy Adams, President Monroe announced in the Monroe Doctrine in 1823 that the American continents were no longer open to colonization, and the United States would look with disfavor on any attempt to extend European control over independent nations in the Western Hemisphere. At the same time, the United States would not interfere in the internal affairs of European nations.
American declaration stated in 1823; established that any attempt of a European country to colonize in the Americas would be considered an unfriendly act by the United States; supported by Great Britain as a means of opening Latin American trade. (p. 764)
The Monroe Doctrine is a U.S. doctrine which, on December 2, 1823, proclaimed that European powers should no longer colonize or interfere with the affairs of the nations of the Americas. The United States planned to stay neutral in wars between European powers and its colonies. However, if these latter types of wars were to occur in the Americas, the United States would view such action as hostile.