"There is not a single cultural element of Central Asian, Eastern European or Caucasian origin in the archaeological culture of the Mittanian area [….] But there is one element novel to Iraq in Mittanian culture and art, which is later on observed in Iranian culture until the Islamisation of Iran: the peacock, one of the two elements of the 'Senmurv', the lion-peacock of the Sassanian art. The first clear pictures showing peacocks in religious context in Mesopotamia are the Nuzi cylinder seals of Mittanian time. There are two types of peacocks: the griffin with a peacock head and the peacock dancer, masked and standing beside the holy tree of life. The veneration of the peacock could not have been brought by the Mittanians from Central Asia or South-Eastern Europe; they must have taken it from the East, as peacocks are the type-bird of India and peacock dancers are still to be seen all over India. The earliest examples are known from the Harappan culture, from Mohenjo-daro and Harappa: two birds sitting on either side of the first tree of life are painted on ceramics. [….] The religious role of the peacock in India and the Indian-influenced Buddhist art in China and Japan need not be questioned" .... "The peacock was therefore subordinated to Indra and connected with the thunderbolt, so that in some Buddhist images Indra is sitting on a peacock throne. It is even possible to trace the peacock as the 'animal of the battle' in Elam till the late 3rd millennium B.C - if it is possible to identify two figured poles from Susa with 'peacock' symbols" ... "Yet the development of the Andronovo culture did not start before 1650-1600 B.C. So that we are forced to accept that the Indo-Aryans in what is now Iran, especially Eastern Iran before 1600 B.C., were under the Indian influence for such a long period that they could have taken over the peacock veneration. In that case, they could not be part of the Andronovo culture, but should have come to Iran centuries before."
January 1, 1970
https://en.wikiquote.org/wiki/Burchard_Brentjes