In this lecture, Professor Kagan traces the development and the power of the Persian empire. He also shows how the Persian empire and the Greek world eventually came into conflict through a few incidents concerning Ionian Greeks in Asia Minor, which eventually turned into the Persian Wars. Professor Kagan ends this lecture with a description of the events of the battle of Marathon in which the Athenians defeated the Persians. Reading assignment: Pomeroy, Burstein, Donlan and Roberts. Ancient Greece. Oxford University Press: New York, 1999, pp. 200-215. Plutarch, The Rise and Fall of the Athens: Aristides, Cimon. Kagan, Donald. "Problems in Ancient History." In The Ancient Near East and Greece. 2nd ed., vol. 1. Prentice-Hall: New York, 1975, chapter 5. Thucydides, The Peloponnesian War, Book I: pp. 89-117.