world greatest civilisation once developed in india in harrapa and mohamjodaro but what was the reason that it went down. harrapa civilisation had about 2 lakh people living there, on the other hand mohonjodaro was even more larger with a more number of people living there . they were highly developed. this fact can be deduced from the fact that when pyramids were being build at that time harrapa was already a developed and organised city. the question is still then why India declined to present status. pre-harrapan civilization had its root most probably in mehergarh in pakistan. people from there spread towards east and understood the power of water, air and fire. this fact is evident from the early vedas, which shows Indra, varuna and agni as major God in contrary to Gods of later vadic period who where brahma, vishnu and Mahesh. although these v