The proposed constitution that opened up the voting rights to all free adult men in 508 B. C. was written by.

Cleisthenes was a man of law from Ancient Greek. He was selected to reform the Constitution of Athens in 508 BC so that it was based in democratic principles. For example, provisions were included to increase the political role of assemblies and to reduce the power of aristrocracies, which was not legitimized by citizens, and also equal rights were established for the people in Athens.
Cleisthenes was denominated the "father of the Athenean democracy".

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