policy, and more ambitious undertakings that would increase the dominant position of his native state. He further extended and fortified the port complex at Piraeus, and "fastened the city [Athens] to the Piraeus, and the land to the sea". Themistocles probably aimed to make Athens the dominant naval power in the Aegean. Indeed, Athens would create the Delian League in 478 BC, uniting the naval power of the Aegean Islands and Ionia under Athenian leadership. Themistocles introduced tax breaks for merchants and artisans, to attract both people and trade to the city to make Athens a great mercantile centre. He also instructed the Athenians to build 20 triremes per year, to ensure that their dominance in naval matters continued. Plutarch reports that Themistocles also secretly proposed to destroy the beached ships of the other Allied navies to ensure complete naval dominance—but was overruled by Aristides and the council of Athens. Fall and exile It seems clear that, towards the end of the decade, Themistocles had begun to accrue enemies, and had become arrogant; moreover his fellow citizens had become jealous of his prestige and power. The Rhodian poet Timocreon was among his most eloquent enemies, composing slanderous drinking songs. Meanwhile, the Spartans actively worked against him, trying to promote Cimon (son of Miltiades) as a rival to Themistocles. Furthermore, after the treason and disgrace of the Spartan general Pausanias, the Spartans tried to implicate Themistocles in the plot; he was, however, acquitted of these charges. In Athens itself, he lost favour by building a sanctuary of Artemis, with the epithet Aristoboulẽ ("of good counsel") near his home, a blatant reference to his own role in delivering Greece from the Persian invasion. Eventually, in either 472 or 471 BC, he was ostracised. In itself, this did not mean that Themistocles had done anything wrong; ostracism, in the words of Plutarch, "was not a penalty, but a way of pacifying and alleviating that jealousy which delights to humble the eminent, breathing out its malice into this disfranchisement." Themistocles first went to live in exile in Argos. However, perceiving that they now had a prime opportunity to bring Themistocles down for good, the Spartans again levelled accusations of Themistocles's complicity in Pausanias's treason. They demanded that he be tried by the 'Congress of Greeks', rather than in Athens, although it seems that in the end he was actually summoned to Athens to stand