Answer:
Realists often trace their intellectual roots to Thucydides’ classic account of the Peloponnesian War in the fifth-century B.C.  It would however take nearly 2,500 years before the study of international politics became an institutionalized academic discipline and for the first classical realists in the newly established field to emerge. Amongst them the German-Jewish émigré to the United States, Hans Morgenthau, came to have the largest impact on the field.
Explanation:
