High Quality Content by WIKIPEDIA articles! The concept of the First World first originated during the Cold War, where it was used to describe countries that were aligned with the United States. These countries were democratic and capitalistic. After the fall of the Soviet Union and the end of the Cold War, the term "First World" took on a new meaning that was more applicable to the times. Since its original definition, the term First World has come to be largely synonymous with developed countries or highly developed countries (depending on which definition is being used).