Ephialtes

Ephialtes (Greek: Ἐφιάλτης, Ephialtēs) was an ancient Athenian politician and an early leader of the democratic movement there. In the late 460s BC, he oversaw reforms that diminished the power of the Areopagus, a traditional bastion of conservatism, and which are considered by many modern historians to mark the beginning of the "radical democracy" for which Athens would become famous. These powers included the scrutiny and control of office holders, and the judicial functions in state trials. He introduced pay for public officeholders, reduced the property qualifications for holding a public office, and created a new definition of citizenship. Ephialtes, however, would not live to participate in this new form of government for long. In 461 BC, he was assassinated, probably at the instigation of resentful oligarchs, and the political leadership of Athens passed to his deputy, Pericles.

Ephialtes first appears in the historical record as the strategos commanding an Athenian fleet in the Aegean sea in 465 BC. Then, in 464 BC, an earthquake hit Sparta, causing a great deal of damage and indirectly resulting in the revolt of the helots. When the Spartans failed to remove the rebels from their base on Mount Ithome, in Messenia, they called for help from cities that were still part of the Hellenic League, an alliance formed in 481 BC against the Persians. The Spartans asked the Athenians for help due to the fact that Athenians had a reputation for being good at siege warfare. Thus spurred much debate upon the Athenians as to what they must do. In August 463 BC, Ephialtes represented those who wished to refuse Sparta's request for military assistance in putting down a helot revolt.Cimon, the most influential Athenian politician and general of the time, was strongly pro-Spartan and advocated sending assistance, arguing that Athenians "ought not to suffer Greece to be lamed, nor their own city to be deprived of her yoke-fellow." Ephialtes, meanwhile, argued that Sparta and Athens were natural rivals, and that Athens should rejoice at Sparta's misfortune rather than help the other city recover. Cimon, however, was victorious in the debate, and set out for Sparta with 4,000 hoplites. However, shortly after the Athenians arrived to help the “conservative and fundamentally xenophobic” Spartans, their assistance was turned down. Subsequently, harmony between Sparta and Athens was broken and Cimon was ostracized for his misjudgment. The end of Cimon’s ascendancy resulted in the emergence of a more radical democratic movement led by Ephialtes.

...
Wikipedia