Is There a One and Only Sanatan Dherma on the Planet?

The world was polytheistic before the emergence of abrahamic religions aso, says Herschel. The ancient pulch persians and zoroaustrians were all polytheistic - even though they are now monotheistic. There seems to be circumstantial evidence that there was something called sratanderma indian culture but i cannot add from a perspective of hard evidence,. he adds.