The caste system as we today know and practise is an invention and tradition of the Vedic pastoralists, not the Indus Valley. It is thought that climate change and perhaps a change in the way rivers flowed brought an end to their civilisation rather than a violent overthrow by an invasion. The Indus Valley Civilisation is still a mystery to us, because their language remains undeciphered and we only have their artefacts to understand them.
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The Vedic pastoralists coming from the West moved onwards and populated the Gangetic plains. As the name suggests, the Indus Valley Civilisation was primarily along the plains of the Indus river. They had engagement with the Harappan and Indus Valley people and interbred with them. They did not recognise the borders as we do today. The Vedic pastoralists, whom we refer to as Aryans, were present in places as far west as Syria. The theory of the Aryan ‘invasion’ has also been discredited. Whereas the Indus Valley Civilisation, including Lothal and Babar Kot in Gujarat, Rakhigarhi and the places today in Pakistan, was urban and built around planned cities, which also had drainage and sanitation. The Vedic people were pastoralists, moving around with their cattle (the word 'Aryavarta' means the ‘turning of the Arya’, in a reference to a large herd being moved around). The Rakhigarhi finding shows that the Harappan culture and the Indus Valley Civilisation were not the source of the Sanskrit language. It has taken this long to determine this because DNA is not preserved well in our hot and wet climate. A sample recovered in 2015 from a Haryana village named Rakhigarhi, which is from a male human who lived 4,500 years ago, shows that he had no part of the same gene as the Aryans (which is known as R1A, and is common to people in northern and eastern Europe, Central Asia and South Asia). However, now it has been conclusively proven that the Indus Valley Civilisation was not Vedic, and came before the Rig Veda. It had been assumed that the beginning of our civilisation came with the Rig Veda, which was written about 3,500 years ago. The discovery of how old the Indus Valley Civilisation was changed the way people thought about the first Indians. Just like Ajanta and Ellora, which were ‘discovered’ by a British officer in 1819 but which had villagers living next to them without wonderment or curiosity for two thousand years. A village right next to it is populated by Punjabis who would have lived there for generations without any interest in the ancient ruins. The place has been beautiful, but deserted.
![compare aryan and harappan cultures compare aryan and harappan cultures](https://s01.sgp1.cdn.digitaloceanspaces.com/article/126900-dxlzjbkqsg-1567749641.jpeg)
That has been true of both times that I have visited. Mohenjo-daro is an ancient Indus Valley Civilisation city.