The Monroe Doctrine was a U.S. foreign policy regarding domination of the Americas in 1823. It stated that further efforts by European nations to colonise land or interfere with states in North or South America would be viewed as acts of aggression, requiring U.S. intervention.
The Doctrine was issued in 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. The United States, working in agreement with Great Britain, wanted to guarantee that no European power would move in.
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, Ronald Reagan and many others.
The intent and impact of the Monroe Doctrine persisted with only minor 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 United States 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.