The Indus-Saraswati Valley civilisation reached its peak around 1,900 BCE. It had been flourishing there for over a millennium from about 3300 BCE. But various proto-Harappan cultures had existed in those fertile plains for almost 4,000 years before that (from about 7,000BCE). At their peak they occupied the entire Indus -Saraswati Valley and stretched as far as the Indo-Gangetic plain. At its peak there were some 1,000 settlements and at least 5 “great” cities that we now know of; Mohenjo-Daro, Harappa, Ganweriwala, Rakhigarhi and Dholavira. None of these are truly coastal and it is not improbable that one or perhaps two “great” coastal cities are now submerged and waiting to be discovered. Only about 10% of the known sites have been investigated and the Indus Valley script – which I call Harappan for convenience – has yet to deciphered.
But by about 1,000 BCE the glories of the civilisation had disappeared; not swept away in one fell swoop by some marauding invaders or by some great pestilence or some cataclysmic natural catastrophe, but gradually as cities and settlements were abandoned and the population gradually thinned out and reduced to a shadow of its heyday. Coming out of the ice-age around 20,000 years ago, sea-levels were almost 100m lower than today. By 7,000 BCE (9,000 years ago) sea levels were already about 30m lower than at present and were rising fast at around 8-10 m/millennium. The settlements in the region were either on the coast or followed the course of the great rivers. It was a 300 – 500 year process of desertification which saw the Saraswati dry up and the creation of the Thar desert.
Where they all went is mainly conjecture but it is likely that they “followed the water”. Some of the sources of the Saraswati would have diverted to flow into the Ganges. That would have taken some people westwards, back along the coast towards the then fertile Persian Gulf, some eastwards across the Indo-Gangetic plain and some southwards along the coast of the Indian subcontinent. Quite possibly some reached the Bay of Bengal and others reached south India and the Indian Ocean. But they did not move into empty spaces. The Indian subcontinent had been continuously settled from the times of homo erectus but by the time of the Toba eruption 74,000 years ago homo erectus had already been replaced by homo sapiens. So when the Harappans moved in, modern humans were already there, but not in large numbers. The earlier settlers probably included the few survivors of a pre-Toba wave of expansion who were then absorbed by later settlers – probably many arrival instances – over some 50,000 years.
In my narrative it is the Harappans and their language which provided the nucleus for, and eventually became, the family of Dravidian languages. In fact it is probable that some of the roots of what became Hinduism came also with them. I would even suggest that the specialisation of functions (administrators, priests, traders, craftsmen and labour) that must have existed in the meticulously planned, water-resourceful, trading cities of the Indus-Saraswati Valley led to the foundation of guilds and a stratified society. That probably laid the foundations of the caste system which, in its perverted form, currently disgraces the subcontinent.
Andrew Robinson looks at the state of the decipherment of the Harappan script in Nature.
Nature 526, 499–501 (22 October 2015) doi:10.1038/526499a.
The Indus civilization flourished for half a millennium from about 2600 bc to 1900 bc. Then it mysteriously declined and vanished from view. It remained invisible for almost 4,000 years until its ruins were discovered by accident in the 1920s by British and Indian archaeologists. Following almost a century of excavation, it is today regarded as a civilization worthy of comparison with those of ancient Egypt and Mesopotamia, as the beginning of Indian civilization and possibly as the origin of Hinduism.
More than a thousand Indus settlements covered at least 800,000 square kilometres of what is now Pakistan and northwestern India. It was the most extensive urban culture of its period, with a population of perhaps 1 million and a vigorous maritime export trade to the Gulf and cities such as Ur in Mesopotamia, where objects inscribed with Indus signs have been discovered. Astonishingly, the culture has left no archaeological evidence of armies or warfare.
Most Indus settlements were villages; some were towns, and at least five were substantial cities … boasted street planning and house drainage worthy of the twentieth century ad. They hosted the world’s first known toilets, along with complex stone weights, elaborately drilled gemstone necklaces and exquisitely carved seal stones featuring one of the world’s stubbornly undeciphered scripts. …
The Indus script is made up of partially pictographic signs and human and animal motifs including a puzzling ‘unicorn’. …..
Whatever their differences, all Indus researchers agree that there is no consensus on the meaning of the script. There are three main problems. First, no firm information is available about its underlying language. Was this an ancestor of Sanskrit or Dravidian, or of some other Indian language family, such as Munda, or was it a language that has disappeared? Linear B was deciphered because the tablets turned out to be in an archaic form of Greek; Mayan glyphs because Mayan languages are still spoken. Second, no names of Indus rulers or personages are known from myths or historical records: no equivalents of Rameses or Ptolemy, who were known to hieroglyphic decipherers from records of ancient Egypt available in Greek. ……
……. Nevertheless, almost every researcher accepts that the script contains too many signs to be either an alphabet or a syllabary (in which signs represent syllables), like Linear B. It is probably a logo-syllabic script — such as Sumerian cuneiform or Mayan glyphs — that is, a mixture of hundreds of logographic signs representing words and concepts, such as &, £ and %, and a much smaller subset representing syllables.
As for the language, the balance of evidence favours a proto-Dravidian language, not Sanskrit. Many scholars have proposed plausible Dravidian meanings for a few groups of characters based on Old Tamil, although none of these ‘translations’ has gained universal acceptance. ……… A minority of researchers query whether the Indus script was capable of expressing a spoken language, mainly because of the brevity of inscriptions. ……. This theory seems unlikely, for various reasons. Notably, sequential ordering and an agreed direction of writing are universal features of writing systems. Such rules are not crucial in symbolic systems. Moreover, the Indus civilization must have been well aware through its trade links of how cuneiform functioned as a full writing system. ……….
What the Harappans wrote and spoke was not Dravidian itself, but it was very likely a proto-Dravidian language, which, with many other influences from what already existed in the South Indian regions they moved into, became the family of Dravidian languages existing today. And it could explain why a Dravidian language can be found today in what is Afghanistan.