Hans Morgenthau was a prominent political scientist and one of the founding figures of the field of international relations. Born in 1904 in Germany, he later emigrated to the United States, where he became a professor at City University of New York. Morgenthau is best known for his book, Politics Among Nations, published in 1948, which laid the groundwork for the realist theory of international relations, emphasizing the role of power and national interest in global politics. Morgenthau's ideas challenged the idealistic views that dominated the study of international relations after World War I. He argued that human nature is inherently self-interested, which leads to conflict and competition among nations. His work has influenced many scholars and policymakers, making him a key figure in understanding the dynamics of international power and diplomacy.