The Indus Civilisation represents the first urbanisation of Indian history.
The origin and authorship of the Indus Civilisation are keenly debated historical questions.
The Indus script has not yet been conclusively deciphered and hence the authorship is not certain.
The graffiti found on the megalithic burial pots of South India and the place names presented are cited to establish the relationship between Indus and Tamil cultures.
The archaeological evidence points to several groups of people living in Tamil Nadu and South India continuously from the Mesolithic period.
One cannot rule out the migration of a few groups from the Indus region.
More research is necessary before arriving at any definite conclusion.
The towns of ancient Tamizhagam such as Arikamedu, Keezhadi and Uraiyur that flourished are part of the second urbanisation of India and these towns are quite different from the Indus cities.
Contemporary Cultures of the Indus Civilisation
Several groups including pastoral people, farmers and hunter-gatherers lived in the Indus region.
The Indus region had villages and large towns.
The population of that time was mixed.
Innumerable communities of hunters-gatherers, pastoral people and farmers, from Kanyakumari to Kashmir and Gujarat to Arunachal Pradesh could have existed during this period.
Their history is also equally important, as cultural and ecological knowledge of all these groups contributed to Indian culture.
While the Indus Civilisation was flourishing in the north-western part of India, several cultures were developing in different parts of India.
In the southern part of the subcontinent, Kerala and Sri Lanka were given to hunting and gathering.
The Harappans who had knowledge of water crafts might have had connections and interactions with South India, but no clear archaeological evidence on this is available.
The northern part of South India, i.e. the Karnataka and Andhra region, had Neolithic cultures, engaged in pastoralism and plough agriculture.
Similarly, the Chalcolithic cultures were prevalent in Deccan and western India, while Neolithic cultures permeated northern India including Kashmir, Ganges valley and central and eastern India.
Thus India was a cultural mosaic during the time of the Harappans.
Decline
The Indus Valley Civilisation declined from about 1900 BCE.
Changes in climate, decline of the trade with the Mesopotamia, and the drying of the river and water resources due to continuous drought are some of the reasons attributed by historians for the decline.
Invasions, floods and shifting of the river course are also cited as reasons for the ruin of Indus civilisation.
In course of time, the people shifted to the southern and eastern directions from the Indus region.
