The Indus Valley in the Vedic Period - Excerpts

from
   - Ramprasad Chanda

It is evident from the hymns of Rgveda that the Aryas were divided into two main classes, the priests and the warriors. Cattle breeding appears to be the main source of their livelihood, cows being the chief wealth. Agriculture was practised to limited extent. A hymn (9,112)  refers to the different professions followed and the crafts practised by the Aryas . Trade finds no place in the list.

So the conclusion that the much maligned Panis were the representatives of an earlier commercial civilization seems irrestible. Among the antiquities unearthed at Mohenjodaro are coins with pictographic legends that indicate very early developement of commercial life in the Indus Valley. The Panis probably represented this pre-historic civilization of the Indus Valley in its las phase when it came into contact with the invading Arya civilization.
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The Arya conquerors who were inferior in material culture either destroyed the cities or allowed them to fall into ruin. Their great god Indra is called Puroha or Purandara, 'sacker of cities'. Like the pre-historic civilization of the Aegean, the pre-historic civilization of the Indus Valley also failed to survive the shock of the Aryan invasion.