The show 's other two sections deal with the on-again , off-again relationship between the cities in the fifth century B.C . , Greece 's glory years , and with the wars they fought : the Persian Wars -LRB- about 500-449 B.C . -RRB- and the Peloponnesian War -LRB- 431 to 404 B.C . -RRB- , in which Sparta defeated Athens , only to fade itself not long after .