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Plutarch (Plut. Cim.).
 
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Athens.

Ephialtes was a democratic reformer in Athens in the early years of the 5th century BCE. Evidence about him is scanty, although we can learn a certain amoung from Plutarch’s biography of Cimon, who was Ephialtes’ main political opponent (Plut. Cim.). Around 462 BCE, Ephialtes brought about changes to the Court of the Areopagus. He sponsored laws and decrees that removed many powers from the Areopagus and gave them to the People’s Court or the Assembly. Because the Areopagus, consisting of former archons serving on the body for life, was the least democratic of Athens’ political institutions, the reforms of Ephialtes can be said to have completed Athens’ transformation into a radical democracy.