The phrase "imperial presidency" entered popular usage in the early 1970s when historian Arthur Schlesinger published a book by that name. Schlesinger was primarily referring to the growth of the President's foreign policy powers. He claimed that the twentieth century had witnessed a new constitutional phenomenon—the "assertion of inherent powers" in foreign policy and other areas that went far beyond what the Framers had intended. This was primarily a function of the Cold War, and one example of the "imperial presidency" Schlesinger cited was President Harry Truman's decision to wage war on the Korean Peninsula without a formal declaration of war by Congress. This marked a major shift in the balance of constitutional powers from Congress to the Presidency, one which had never been restored.

President Lyndon's Johnson's decision to escalate the war in Vietnam was also an example of the imperial presidency. This decision, carried out with fairly obliging congressional approval—always after the fact—was for Schlesinger a substantial assertion of the presidential prerogative, one which resembled that of a monarch. But by far, the most egregious example of the imperial presidency was that of Richard Nixon. Schlesinger's book was published in the midst of Watergate, and he argued that Nixon had taken the imperial presidency to its logical conclusion by using his powers against supposed domestic enemies. He used his powers to spy on rivals, to break in and steal confidential documents, and, of course, to pay off potential blackmailers. Schlesinger later wrote that the "Imperial Presidency reached a twentieth century climax with Nixon." Though subsequent presidents would assert powers that dramatically (and perhaps dangerously) expanded the powers of the office, Nixon remains the paradigmatic example of the imperial presidency.