When the Helots revolted from Sparta around 465 BC, they fortified themselves on the slopes of Mt. Ithome after losing in Laconia. The Spartans were unable to dislodge them, and at this point called for help from their allies in the Persian War, and among them, Athens. In the Athenian Assembly, Cimon urged support for the Spartans but met fierce resistance from new men such as Ephialtes who were working for a more democratic and independent Athens free from Spartan influence. Cimon narrowly won the vote and led a strong hoplite force to aid Sparta, but the Spartans dismissed the relieving army, suspicious of their intentions.
The reaction in Athens was furious; Cimon was discredited and was ostracised in 461 BC. His main opponent was Ephialtes. Ephialtes was able to carry a series of laws that changed the character of Athenian democracy. The most important reform he carried was the curtailment of The Areopagus, an aristocratic dominated institution that the Archons joined upon the completion of their year in office. However, it is unclear as to what powers exactly the Council lost; Aristotle and other writers never made it precisely clear in their writings. In the 6th century BC the Areopagus had been the guardian of the constitution, but the reforms of Cleisthenes had shifted the balance of power to The Council of Five Hundred and the Assembly. It was probably around 487 BC when the lot (randomisation) was introduced to pick public officials (Including Archons) that the Areopagus began to decline. From this period, someone’s wealth and family status was irrelevant to seeking office as the process was done by random.
The emphasis on the new, more developed democracy of Athens on the people’s control of the executive suggests that magistrates had previously been influenced by the Areopagus. New powers were now explicitly given to the people. The jury courts were reorganised on a popular basis and court decisions were no longer rested with the magistrates but with the jurors, who were paid for their services. That principle was later applied to the Council of Five Hundred and to all offices of state; no citizen was to be barred from state service by poverty. All officials had to undergo an examination in a people’s court at the end of their year in office, and public auditors were annually appointed to examine accounts, creating a robust level of accountability for the cities politicians. The threat of Ostracism and the greater transparency in government ensured political corruption was positively challenged by Ephialtes' reforms. It is also significant that from the 450s important decrees of the Assembly and the summary accounts of public works were normally inscribed on stone and set up on the Acropolis or in some other public place where people could see them, suggesting a high level of public awareness of politics in the city.
Ephialtes was consequently assassinated as a result of his reforms, but his political revolution had been consolidated, and the changes he introduced were permanent.