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Monument of the Eponymous Heroes Across the street from the Metroon lie the remains of the Monument of the Eponymous Heroes (Fig. 21). When Kleisthenes created the democracy in 508/7 B.C., he assigned ... New tribes were created and new heroes added from time to time in order to flatter powerful rulers in the Hellenistic and Roman periods; the number of tribes -- and therefore heroes -- fluctuated between ten and thirteen.