This article presents a brief history of the Monroe Doctrine since its articulation in 1823. First conceived as a statement in opposition to European intrusions in the Americas, it became under President Theodore Roosevelt a justification for U.S. intervention. To cultivate Latin American trade and goodwill during the Great Depression and the Second World War, Franklin Roosevelt's administration accepted the principle of nonintervention. Later with the onset of the Cold War, perceived international imperatives led to a series of new interventions in countries such as Guatemala, Cuba, the Dominican Republic, and Chile. Though typically couched in idealistic rhetoric emphasizing Pan-American commitments to solidarity and democracy, the various versions of the Monroe Doctrine consistently served U.S. policy makers as a means for advancing what they understood as national strategic and economic interests.