Decelean War or Ionian War: name of the last part of the Peloponnesian War (431-404). The first phase, the Archidamian War, had ended in 421 with something that came close to an Athenian victory. However, Athenian diplomatic mistakes, Spartan intransigence, and a disastrous Athenian attempt to conquer the island of Sicily changed the balance of power. After this entr'acte, the Spartans declared war again in 413 and occupied the town of Decelea near Athens; with Persian money, they built a navy and provoked revolutions in Athens' possessions in Ionia. In 404, Athens surrendered.
Many people, including the Athenians, believed that after the Sicilian disaster, the end of the Delian League was near. Athens had lost much money, many ships, and its best soldiers. Worse, they had no experienced leaders anymore: Alcibiades was in exile and lived in Sparta, Demosthenes, Lamachus, and Nicias were dead, and the popular Hyperbolus had been ostracized. To cope with this lack of experienced leadership, the Athenians appointed ten wise men (including the playwright Sophocles) to act as probouloi, which meant that they had to give advice and propose measures to overcome the present crisis.
The crisis, however, was grave. The Spartan king Agis II had occupied the village of Decelea and had built a strong fort - following an advice of Alcibiades, it was rumored, as if the Spartans could not think for themselves. The countryside was now under constant threat and the Athenians no longer had access to the silver mines of Laureion. Meanwhile, the Peloponnesian League dared to send a fleet to the Aegean Sea, consisting of Syracusan vessels (commanded by Hermocrates) and Corinthian ships. The Persian satraps Tissaphernes of Lydia and Pharnabazus of Hellespontine Phrygia offered money to Sparta, both hoping to achieve military support for the great king's aims in return. However, the Spartans were able to mess up this splendid opportunity.
When Chios, one of the islands in the Athenian alliance, revolted, the Spartans were unable to support the rebels. They still had insufficient experience at sea, so they turned to an Athenian for help. Alcibiades, who had been caught sleeping with king Agis' wife and wanted to leave Sparta, accepted the command of a Spartan naval force, and was able to reach Chios, where he reinforced the insurrectionists. The revolt immediately spread to other towns, including Miletus, the largest Greek city in Asia.
At this moment, in 412, the Spartans concluded their first treaty with king Darius II Nothus, who offered pay for the Spartan navy. (The treaty was later revised.) Tissaphernes was to be the king's agent, but he believed that an unconditional alliance with Sparta was not in the interests of Persia, so he delayed payments and more than once threatened to negotiate with Athens. In the meantime, Sparta had to help the great king by arresting Amorges, the rebel who had been supported by Athens.
The Persian-Spartan coalition ultimately was to bring down Athens, but the city was not defeated yet. Athens had faced a similar coalition in 461-448 and back then, it had achieved remarkable results. However, after the Sicilian disaster, this was no longer possible. Still, the Athenians responded to the challenge and founded a base on the isle of Samos. They started to besiege Chios and landed at Miletus, where they defeated their enemies in an open battle. Unfortunately, their inexperienced commander Phrynichus hesitated to exploit his victory, and the Spartans responded by taking the isle of Rhodes.
At this point, Alcibiades told the Athenians that he would bring over the great king to their side if Athens accepted him again and gave up its democracy. Indeed, a man named Peisander conducted an extreme oligarchic coup in Athens in 411 (text). Among the other leaders of the Four Hundred were Antiphon, who sincerely believed that oligarchy was preferable to democracy, and a general named Theramenes, son of Hagnon, who believed that if the suspension of democracy would bring Persian support, it was worth a try. Others joined because an oligarchy was cheaper, and Athens lacked money now that half its empire was rebellious. From the very first start, the oligarchs were divided.
A new crisis faced the Athenians when the cities near the Hellespont revolted, including Byzantium and Calchedon on both sides of the Bosphorus. This seriously imperiled the Athenian grain supply, and the men on board of the Athenian fleet -led by Thrasybulus, a friend of Alcibiades- declared that they now were the demos (the people's assembly) and recalled Alcibiades. More or less at the same time, a Spartan fleet reached and occupied Euboea, where the Athenians had left their cattle. Under these critical circumstances, the Four Hundred were replaced by the moderate oligarchy that had been proposed by Theramenes. Power now was in the hands of the Five Thousand, which meant those men who could "serve the state with a horse or a shield".
Meanwhile, the Spartans decided to move the war from Ionia and Euboea to the Hellespont, where they could cut off the grain supply of Athens and would receive support from Pharnabazus, who said he wanted to support Sparta unconditionally. Admiral Mindarus brought the Spartan fleet to the north, but was defeated at Cynossema by the Athenians, who were commanded by Thrasybulus and Thrasyllus.
This was a lift to Athenian morale, and Theramenes immediately exploited it by opening a new front in the Cyclades, where he subdued several rebellious islands and filled the Athenian treasury. He continued to Macedonia, where he taught king Archelaus how to besiege Pydna, and received a handsome amount of money in return. (At this point, Thucydides' History breaks off, and we are left to the Xenophon's Hellenica and Diodorus' Library.) When the year 410 started, all Athenian commanders -Alcibiades, Theramenes, Thrasybulus, and Thrasyllus- gathered in the Hellespont, where they defeated the Spartan navy near Cyzicus. Its admiral Mindarus was killed in action, and the Spartans sued for peace.
Historians have criticized the Athenians that they did not accept this offer, but as the popular leader Cleophon pointed out, the Spartan proposal was not a very good one: both parties would keep the cities it controlled, give up garrisons in enemy territory, and would exchange prisoners. This implied that Athens had to give up control of many important towns and the Bosphorus. In 421, Sparta had been unwilling to fulfill the terms of the Peace of Nicias; if Sparta again broke its promise, the Athenians would be in great danger. Without control of Euboea, the Bosphorus, and the Hellespont, Cleophon said, any peace treaty was unacceptable. The rejection of the peace offer may have been the moment when democracy was restored.
Now, the war came to a standstill. Sparta was unable to strike and the Athenian democrats were not happy with the successful admirals: after all, Alcibiades, Theramenes, Thrasybulus, and Thrasyllus had collaborated with the oligarchs. They were left in office, but were not reinforced. Still, in 409, they recovered some ground in Ionia, and in 408 they regained control of the Bosphorus. In 407, Alcibiades returned to Athens, where he presided over the celebration of the Mysteries in Eleusis. It seemed as if the Athenians were winning the war after all.
But almost immediately, things went wrong. Alcibiades' deputy Antiochus, a brave but inexperienced man who should never have been appointed, was defeated in a naval engagement at Notion. Immediately, the Athenians sent Alcibiades away from their city again, and this time for good. The battle itself was not very important, but gave new self-confidence to the Spartans, who had finally found a capable admiral: Lysander. His greatest strength was that he had access to people who would help him. As lover of Agesilaus, the brother of king Agis, he was sufficiently supported at home, and he was lucky to find a new satrap in Lydia, prince Cyrus the Younger, the son of king Darius. He had orders to support Sparta unconditionally; Tissaphernes, who had sometimes threatened to support Athens, was temporarily removed from office.
In fact, Athens was now doomed. In 406, it was able to defeat the Spartans for the last time in a large naval battle at the Arginusae, but a gathering storm prevented the victorious admirals from picking the survivors and the dead from the water. Back home, they were condemned to death.
Again, Athens had no experienced commanders. In 405, Lysander's Spartan navy was active in the Hellespont again, the Athenians were defeated at the Aigospotamoi, and their entire fleet was destroyed. The war was now decided: what was left, was the siege of Athens. The Spartan king Agis left Decelea, his colleague Pausanias arrived with an army from the Peloponnese, and Lysander blocked Piraeus. During the winter, Theramenes conducted negotiations, and accepted what was inevitable (text).
In April 404, the Athenians disbanded the Delian League, what was left of the fleet was surrendered, Athens joined the Peloponnesian League, and a regime of thirty oligarchs -foremost among whom were the radical Critias and the moderate Theramenes- was to rule the city (text). According to Xenophon, the Spartans "tore down the Long walls among scenes of great joy and to the music of flute girls".note[Xenophon, Hellenica 2.2.24.]