<P> The Monroe Doctrine was a United States policy of opposing European colonialism in the Americas beginning in 1823 . It stated that further efforts by European nations to take control of any independent state in North or South America would be viewed as "the manifestation of an unfriendly disposition toward the United States ." At the same time, the doctrine noted that the U.S. would recognize and not interfere with existing European colonies nor meddle in the internal concerns of European countries . The Doctrine was issued on December 2, 1823 at a time when nearly all Latin American colonies of Spain and Portugal had achieved, or were at the point of gaining, independence from the Portuguese and Spanish Empires . </P> <P> President James Monroe first stated the doctrine during his seventh annual State of the Union Address to Congress . The term "Monroe Doctrine" itself was coined in 1850 . By the end of the 19th century, Monroe's declaration was seen as a defining moment in the foreign policy of the United States and one of its longest - standing tenets . It would be invoked by many U.S. statesmen and several U.S. presidents, including Ulysses S. Grant, Theodore Roosevelt, John F. Kennedy, and Ronald Reagan . The intent and impact of the Monroe Doctrine persisted with only small variations for more than a century . Its stated objective was to free the newly independent colonies of Latin America from European intervention and avoid situations which could make the New World a battleground for the Old World powers, so that the U.S. could exert its own influence undisturbed . The doctrine asserted that the New World and the Old World were to remain distinctly separate spheres of influence, for they were composed of entirely separate and independent nations . </P>

The american policy warning against future european colonization of the western hemisphere was