ABSTRACT
Greek Civilization begins with a great poem celebrating war, the Iliad. War represented a structural component of the Greco-Roman world, as much or more than slavery or agriculture; from Herodotus to Xenophon and from Thucydides to Polybius, Greek historiography is above all political-military history. Before the Persian Wars in the early fifth century, Greece presented a panorama of local, seasonal, and quantitatively limited warfare. The institutions of international law that develop in the seventh and sixth centuries are directly derived from these experiments and achievements of early Greece that are reflected in the epics. Things were simpler when military aid was lent to an ally fighting against a third state with whom peaceful relations were maintained by means of a post-war non-aggression treaty (long-term spondai), or against a state with whom there was no relationship at all. Relations between Athens and Sparta during the Peace of Nicias, concluded in 421 after the first phase of the Peloponnesian War.
