King Chandragupta took the territory into Indian control.
The Greek city-states occupied by, or threatened by, expansion of the Persian Empire in the eastern Mediterranean littoral.
military conquest
There were also the Sumerian, Chaldean, and Assyrian Empires , as well as the kingdom of Egypt. But these weren't the major Empires.
It limited Persian expansion westwards, and left the Greek city-states to go back to fighting each other.
To the people involved, soldiers and civilians, it was important to them as it affected their lives greatly. In the grand sweep of thousands of years of history, it was just another in the thousands of wars which the human race seems intent on inflicting on itself.
Athens became part of Greek resistance to Persian expansion, originally a couple of dozen cities, and then growing to a couple of hundred.
It put an end to Persian expansion to the west and led to the contest for power in the Greek world between Athens and its empire and the Spartan-led Peloponnesian League.
The main reason was expansion of the Persian Empire into the Greek city states of Asia Minor and by extension to Greece proper. Herodotus is the best classical source
Peace between the Greeks and Persian nations , an expansion of Greek literature , philosophies , ideas , culture and democratic government , commerce and trade .
Greek conquered the neighboring empires
Greek conquered the neighboring empires
It stopped any further Persian expansion of control to the west and developed the virtue of freedom over tyranny.