What governmental body did Cleisthenes replace with a Council of 500 in Athens?

Cleisthenes replaced the Council of 400 with the Council of 500 in Athens. This change was part of his reforms aimed at enhancing democratic governance in the city-state. The Council of 400 was initially established by Solon and was comprised of members selected from the aristocratic class, which limited broader representation.

By instituting the Council of 500, Cleisthenes expanded representation in Athenian government to include a greater number of citizens, ensuring that each of the ten tribes of Athens contributed to the council. Each tribe provided 50 members, making the council more representative of the entire population, rather than an elite segment. This shift was significant in promoting direct democracy, as it allowed for more citizen involvement in decision-making processes and laid the foundations for Athenian democracy as it is known today. The establishment of the Council of 500 facilitated the organization of the Assembly, where citizens could vote on various matters affecting the city-state, thus enhancing the political power of the average citizen.