Ancient Greece: Second (=Great) Peloponnesian War (431-404 BC): Archidamian War

Thucydides says that the underlying cause of the war was that Sparta feared the growth of Athenian power. It is probable, however, that it was not so much as Athens’ power that Sparta feared but rather the use of that power to challenge Sparta’s hegemony over the other Greek states.

Sparta and its allies, with the exception of Corinth, were almost exclusively land-based powers, able to summon large land armies that were very nearly unbeatable. The Athenian Empire, although based in the peninsula of Attica, spread out across the islands of the Aegean Sea. Athens’ immense wealth was derived from the tribute paid by these islands, and the empire was maintained through naval power. Sparta had about 30,000 hoplites, 2000 cavalry and 100 ships (mainly Corinthian); Athens had about 13,000 hoplites, 1200 cavalry and 300 ships. The two sides, a land power and a sea power respectively, could not sensibly meet to fight a decisive battle.

Pericles’ strategy was based on his belief that in a land battle Athens would be defeated by Sparta. Constructing the Long Walls had made Athens and its port Piraeus into a single fortified area. The rest of Attica was to be abandoned and people moved to safety behind the walls. The flocks and herds were transported to Euboea. Crucially, the Athenians’ control of the sea would ensure the collection of the tribute money to buy and import food and other resources. A navy offensive would be used to wear Sparta down and force her to sue for peace.

The Spartan army would thus be able to march freely into Attica and approach the city walls. But at the time the Spartans had not developed the concepts of siegecraft and fortification: they needed their battles to be quick and decisive and not to have to spend long periods on military campaigns as they had to return home for provisions and to maintain control of the helots. (Sparta itself was garrisoned but unfortified.)

Sparta’s strategy therefore was to use their army to make annual invasions of Attica to deny the Athenians’ access to the produce of their land outside the city walls. Meanwhile, Sparta’s allies would be building and equipping ships so that eventually they could enter the Aegean and encourage Athens’ subjects in the Delian League to revolt.

Archidamian War (431-421 BC)

The period of the first ten years of the conflict is called the Archidamian War after the Spartan king Archidamus II (Eurypontid; r.476-427 BC). During the first few years the war fell into its predicted pattern. The Spartans invaded Attica five times between 431 and 425 BC; the longest of these invasions, in 430 BC, only lasted for forty days. At the same time the Athenians used their naval power to attack around the edges of Spartan territory.