Coup of 411 BC
In 413 BC, a massive Athenian expedition force was completely obliterated in Sicily. In the wake of this defeat, Athens found itself facing a crisis of unprecedented magnitude. Cities throughout its Aegean empire began to rebel, and a Peloponnesian fleet sailed to assist them. Seeking to contain the crisis, Athens tapped its reserve fund to rebuild its fleet and dispatched what ships it had to establish an advance naval base at Samos.
In this general atmosphere of crisis, aristocrats at Athens who had long desired to overthrow the democracy there began to agitate publicly for a change of government, and formed a conspiracy to bring an oligarchy to power in Athens. Their plans included recalling Alcibiades, who had been exiled by the democratic government. These oligarchs initiated their plans at Samos, where they successfully encouraged a number of Samian oligarchs to begin a similar conspiracy.
A dispute has arisen among modern historians over Thrasybulus' involvement in this plot. Donald Kagan has suggested that Thrasybulus was one of the founding members of the scheme and was willing to support moderate oligarchy, but was alienated by the extreme actions taken by the plotters. R.J. Buck, on the other hand, maintains that Thrasybulus was probably never involved in the plot, possibly because he was absent from Samos at the time of its inception.
Upon their return to Athens, the conspirators succeeded in ending democratic rule and imposing an oligarchy of 400 rulers. At Samos, however, the coup did not go forward so smoothly. Samian democrats learned of the conspiracy and notified four prominent Athenians, the generals Leon and Diomedon, Thrasybulus, and Thrasyllus, at that time a hoplite in the ranks. With the support of these men and the Athenian soldiers in general, the Samian democrats were able to defeat the conspirators when they attempted to seize power.
A ship was dispatched to Athens to notify the city of this success against the oligarchs. Upon its arrival, however, the crew was arrested, as the news of a democratic victory was far from welcome to the new oligarchic government. Learning of this, the army at Samos deposed its generals and elected new generals who were believed to be more steadfast in their support of democracy, Thrasybulus and Thrasyllus among them. The army, stating that they had not revolted from the city but that the city had revolted from them, resolved to stand by the democracy while continuing to prosecute the war against Sparta.
One of the first actions Thrasybulus took as general was to bring about the recall of Alcibiades, a policy that he had supported since before the coup. After persuading the sailors to support his plan, Thrasybulus sailed to retrieve Alcibiades and returned with him to Samos. The aim of this policy was to win away Persian support from the Spartans, as it was believed that Alcibiades had great influence with Tissaphernes. Alcibiades was elected as general alongside Thrasybulus and the others. Shortly after this, following the revolt of Euboea, the government of the 400 at Athens was overthrown and replaced by a broader oligarchy, which would eventually give way to democracy.
Read more about this topic: Thrasybulus