The Indus Valley Civilization (IVC) was a Bronze Age civilization (3300–1300 BCE; mature period 2600–1900 BCE) located in the western region of South Asia, and spread over what are now Pakistan, northwest and western India, eastern Afghanistan, and southeastern Iran. Flourishing in the Indus River basin, the civilization extended east into the Ghaggar-Hakra River valley and the upper reachesGanges-Yamuna Doab; it extended west to the Makran coast of Balochistan, north to northeastern Afghanistan and south to Daimabadin Maharashtra. The civilization was spread over some 1,260,000 km², making it the largest ancient civilization.
The Indus Valley is one of the world’s earliest urban civilizations, along with its contemporaries, Mesopotamia and Ancient Egypt. At its peak, the Indus Civilization may have had a population of well over five million. Inhabitants of the ancient Indus river valley developed new techniques in handicraft (carnelian products, seal carving) and metallurgy (copper, bronze, lead, and tin). The civilization is noted for its cities built of brick, roadside drainage system, and multistoried houses.
The Indus Valley Civilization is also known as the Harappan Civilization, as the first of its cities to be unearthed was located at Harappa, excavated in the 1920s in what was at the time the Punjab province of British India (now in Pakistan). Excavation of Harappan sites has been ongoing since 1920, with important breakthroughs occurring as recently as 1999. There were earlier and later cultures, often called Early Harappan and Late Harappan, in the same area of the Harappan Civilization. The Harappan civilisation is sometimes called the Mature Harappan culture to distinguish it from these cultures. Up to 1999, about 1,056 cities and settlements have been found, of which 96 sites have been excavated mainly in the general region of the Indus river and its tributaries. Among the settlements were the major urban centres of Harappa, Mohenjo-daro (UNESCO World Heritage Site), Ganweriwala, Dholavira, and Rakhigarhi.
The Harappan language is not directly attested and its affiliation is uncertain since the Indus script is still undeciphered. A relationship with theDravidian or Elamo-Dravidian language family is favored by most accounts.
Discovery and excavation of Indus Valley Civilization
The ruins of Harrappa were first described in 1842 by Charles Masson in his Narrative of Various Journeys in Balochistan, Afghanistan, and the Punjab, where locals talked of an ancient city extending “thirteen cosses” (about 25 miles), but no archaeological interest would attach to this for nearly a century.
In 1856, General Alexander Cunningham, later director general of the archeological survey of northern India, visited Harappa where the British engineers John and William Brunton were laying the East Indian Railway Company line connecting the cities of Karachi and Lahore. John wrote: “I was much exercised in my mind how we were to get ballast for the line of the railway”. They were told of an ancient ruined city near the lines, called Brahminabad. Visiting the city, he found it full of hard well-burnt bricks, and, “convinced that there was a grand quarry for the ballast I wanted”, the city of Brahminabad was reduced to ballast. A few months later, further north, John’s brother William Brunton’s “section of the line ran near another ruined city, bricks from which had already been used by villagers in the nearby village of Harappa at the same site. These bricks now provided ballast along 93 miles (150 km) of the railroad track running from Karachi to Lahore”.
In 1872–75 Alexander Cunningham published the first Harappan seal (with an erroneous identification as Brahmi letters). It was half a century later, in 1912, that more Harappan seals were discovered by J. Fleet, prompting an excavation campaign under Sir John Hubert Marshall in 1921–22 and resulting in the discovery of the civilization at Harappa by Sir John Marshall, Rai Bahadur Daya Ram Sahni and Madho Sarup Vats, and at Mohenjo-daro by Rakhal Das Banerjee, E. J. H. MacKay, and Sir John Marshall. By 1931, much of Mohenjo-Daro had been excavated, but excavations continued, such as that led by Sir Mortimer Wheeler, director of the Archaeological Survey of India in 1944. Among other archaeologists who worked on IVC sites before the partition of the subcontinent in 1947 were Ahmad Hasan Dani, Brij Basi Lal, Nani Gopal Majumdar, and Sir Marc Aurel Stein.
Following the Partition of India, the bulk of the archaeological finds were inherited by Pakistan where most of the IVC was based, and excavations from this time include those led by Sir Mortimer Wheeler in 1949, archaeological adviser to the Government of Pakistan. Outposts of the Indus Valley civilization were excavated as far west as Sutkagan Dor in Baluchistan, as far north as at Shortugai on the Amu Darya (the river’s ancient name was Oxus) in current Afghanistan, as far east as at Alamgirpur, Uttar Pradesh, India and as far south as at Malwan, Surat Dist., India.
Chronology of Indus Valley Civilization
|7000 – 5500 BCE||
Mehrgarh I (aceramic Neolithic)
|Early Food Producing Era
Mehrgarh II-VI (ceramic Neolithic)
Harappan 1 (Ravi Phase)
Harappan 2 (Kot Diji Phase, Nausharo I, Mehrgarh VII)
|2600-1900||Mature Harappan (Indus Valley Civilization)
Harappan 3A (Nausharo II)
Geography of Indus Valley Civilization
The Indus Valley Civilization encompassed most of Pakistan, extending from Balochistan to Sindh, and extending into modern day Indian states of Gujarat, Rajasthan, Haryana, and Punjab, with an upward reach to Rupar on the upper Sutlej. The geography of the Indus Valley put the civilizations that arose there in a highly similar situation to those in Egyptand Peru, with rich agricultural lands being surrounded by highlands, desert, and ocean. Recently, Indus sites have been discovered in Pakistan’s northwestern Frontier Province as well. Other IVC colonies can be found in Afghanistan while smaller isolated colonies can be found as far away as Turkmenistan and in Gujarat. Coastal settlements extended fromSutkagan Dor in Western Baluchistan to Lothal in Gujarat. An Indus Valley site has been found on the Oxus River at Shortughai in northern Afghanistan, in the Gomal River valley in northwestern Pakistan, at Manda,Jammu on the Beas River near Jammu, India, and at Alamgirpur on the Hindon River, only 28 km from Delhi. Indus Valley sites have been found most often on rivers, but also on the ancient seacoast, for example, Balakot, and on islands, for example, Dholavira.
There is evidence of dry river beds overlapping with the Hakra channel in Pakistan and the seasonal Ghaggar River in India. Many Indus Valley (or Harappan) sites have been discovered along the Ghaggar-Hakra beds. Among them are: Rupar, Rakhigarhi, Sothi, Kalibangan, and Ganwariwala. According to J. G. Shaffer and D. A. Lichtenstein, the Harappan Civilization “is a fusion of the Bagor, Hakra, and Koti Dij traditions or ‘ethnic groups’ in the Ghaggar-Hakra valley on the borders of India and Pakistan”.
According to some archaeologists, more than 500 Harappan sites have been discovered along the dried up river beds of the Ghaggar-Hakra River and its tributaries, in contrast to only about 100 along the Indus and its tributaries; consequently, in their opinion, the appellation Indus Ghaggar-Hakra civilisation or Indus-Saraswati civilisation is justified. However, these politically inspired arguments are disputed by other archaeologists who state that the Ghaggar-Hakra desert area has been left untouched by settlements and agriculture since the end of the Indus period and hence shows more sites than found in the alluvium of the Indus valley; second, that the number of Harappan sites along the Ghaggar-Hakra river beds have been exaggerated and that the Ghaggar-Hakra, when it existed, was a tributary of the Indus, so the new nomenclature is redundant. “Harappan Civilization” remains the correct one, according to the common archaeological usage of naming a civilization after its first findspot.
Background- Early Harappan
The Early Harappan Ravi Phase, named after the nearby Ravi River, lasted from circa 3300 BCE until 2800 BCE. It is related to the Hakra Phase, identified in the Ghaggar-Hakra River Valley to the west, and predates the Kot Diji Phase (2800-2600 BCE, Harappan 2), named after a site in northern Sindh, Pakistan, near Mohenjo Daro. The earliest examples of the Indus script date from around 3000 BCE.
The mature phase of earlier village cultures is represented by Rehman Dheri and Amri in Pakistan. Kot Diji (Harappan 2) represents the phase leading up to Mature Harappan, with the citadel representing centralised authority and an increasingly urban quality of life. Another town of this stage was found at Kalibangan in India on the Hakra River.
Trade networks linked this culture with related regional cultures and distant sources of raw materials, including lapis lazuli and other materials for bead-making. Villagers had, by this time, domesticated numerous crops, including peas, sesame seeds, dates, and cotton, as well as various animals, including the water buffalo. Early Harappan communities turned to large urban centres by 2600 BCE, from where the mature Harappan phase started.
By 2600 BCE, the Early Harappan communities had been turned into large urban centres. Such urban centres include Harappa, Ganeriwala, Mohenjo-Daro in modern day Pakistan, and Dholavira, Kalibangan, Rakhigarhi, Rupar, and Lothal in modern day India. In total, more than 1,052 cities and settlements have been found, mainly in the general region of the Indus Rivers and their tributaries.
Cities of Indus Valley Civilization
A sophisticated and technologically advanced urban culture is evident in the Indus Valley Civilization making them the first urban centres in the region. The quality of municipal town planning suggests the knowledge of urban planning and efficient municipal governments which placed a high priority on hygiene, or, alternatively, accessibility to the means of religious ritual.
As seen in Harappa, Mohenjo-Daro and the recently partially excavated Rakhigarhi, this urban plan included the world’s first known urbansanitation systems: see hydraulic engineering of the Indus Valley Civilization. Within the city, individual homes or groups of homes obtained water from wells. From a room that appears to have been set aside for bathing, waste water was directed to covered drains, which lined the major streets. Houses opened only to inner courtyards and smaller lanes. The house-building in some villages in the region still resembles in some respects the house-building of the Harappans.
The ancient Indus systems of sewerage and drainage that were developed and used in cities throughout the Indus region were far more advanced than any found in contemporary urban sites in the Middle East and even more efficient than those in many areas of Pakistan and India today. The advanced architecture of the Harappans is shown by their impressive dockyards, granaries, warehouses, brick platforms, and protective walls. The massive walls of Indus cities most likely protected the Harappans from floods and may have dissuaded military conflicts.
The purpose of the citadel remains debated. In sharp contrast to this civilization’s contemporaries, Mesopotamia and Ancient Egypt, no large monumental structures were built. There is no conclusive evidence of palaces or temples—or of kings, armies, or priests. Some structures are thought to have been granaries. Found at one city is an enormous well-built bath (the “Great Bath”), which may have been a public bath. Although the citadels were walled, it is far from clear that these structures were defensive. They may have been built to divert flood waters.
Most city dwellers appear to have been traders or artisans, who lived with others pursuing the same occupation in well-defined neighbourhoods. Materials from distant regions were used in the cities for constructing seals, beads and other objects. Among the artifactsdiscovered were beautiful glazed faïence beads. Steatite seals have images of animals, people (perhaps gods), and other types of inscriptions, including the yet un-deciphered writing system of the Indus Valley Civilization. Some of the seals were used to stamp clay on trade goods and most probably had other uses as well.
Although some houses were larger than others, Indus Civilization cities were remarkable for their apparent, if relative, egalitarianism. All the houses had access to water and drainage facilities. This gives the impression of a society with relatively low wealth concentration, though clear social levelling is seen in personal adornments.
Authority and governance
Archaeological records provide no immediate answers for a center of power or for depictions of people in power in Harappan society. But, there are indications of complex decisions being taken and implemented. For instance, the extraordinary uniformity of Harappan artifacts as evident in pottery, seals, weights and bricks. These are the major assumptions:
- There was a single state, given the similarity in artifacts, the evidence for planned settlements, the standardised ratio of brick size, and the establishment of settlements near sources of raw material.
- There was no single ruler but several: Mohenjo-daro had a separate ruler, Harappa another, and so forth.
- Harappan society had no rulers, and everybody enjoyed equal status.
Technology used in Indus Valley Civilization
The people of the Indus Civilization achieved great accuracy in measuring length, mass, and time. They were among the first to develop a system of uniform weights and measures. A comparison of available objects indicates large scale variation across the Indus territories. Their smallest division, which is marked on an ivory scale found in Lothal, was approximately 1.704 mm, the smallest division ever recorded on a scale of the Bronze Age. Harappan engineers followed the decimal division of measurement for all practical purposes, including the measurement of mass as revealed by their hexahedron weights.
These chert weights were in a ratio of 5:2:1 with weights of 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, 100, 200, and 500 units, with each unit weighing approximately 28 grams, similar to the English Imperial ounce or Greek uncia, and smaller objects were weighed in similar ratios with the units of 0.871. However, as in other cultures, actual weights were not uniform throughout the area. The weights and measures later used in Kautilya’s Arthashastra (4th century BCE) are the same as those used in Lothal.
Harappans evolved some new techniques in metallurgy and produced copper, bronze, lead, and tin. The engineering skill of the Harappans was remarkable, especially in building docks.
In 2001, archaeologists studying the remains of two men from Mehrgarh, Pakistan, made the discovery that the people of the Indus Valley Civilization, from the early Harappan periods, had knowledge of proto-dentistry. Later, in April 2006, it was announced in the scientific journal Nature that the oldest (and first early Neolithic) evidence for the drilling of human teeth in vivo (i.e., in a living person) was found in Mehrgarh. Eleven drilled molar crowns from nine adults were discovered in a Neolithic graveyard in Mehrgarh that dates from 7,500-9,000 years ago. According to the authors, their discoveries point to a tradition of proto-dentistry in the early farming cultures of that region.
A touchstone bearing gold streaks was found in Banawali, which was probably used for testing the purity of gold (such a technique is still used in some parts of India).
Arts and crafts (Indus Valley Civilization)
Various sculptures, seals, pottery, gold jewelry, and anatomically detailed figurines in terracotta, bronze, and steatite have been found at excavation sites.
A number of gold, terra-cotta and stone figurines of girls in dancing poses reveal the presence of some dance form. Also, these terra-cotta figurines included cows, bears, monkeys, and dogs. The animal depicted on a majority of seals at sites of the mature period has not been clearly identified. Part bull, part zebra, with a majestic horn, it has been a source of speculation. As yet, there is insufficient evidence to substantiate claims that the image had religious or cultic significance, but the prevalence of the image raises the question of whether or not the animals in images of the IVC are religious symbols.
Sir John Marshall is known to have reacted with surprise when he saw the famous Indus bronze statuette of a slender-limbed dancing girl in Mohenjo-Daro:
… When I first saw them I found it difficult to believe that they were prehistoric; they seemed to completely upset all established ideas about early art, and culture. Modeling such as this was unknown in the ancient world up to the Hellenistic age of Greece, and I thought, therefore, that some mistake must surely have been made; that these figures had found their way into levels some 3000 years older than those to which they properly belonged. … Now, in these statuettes, it is just this anatomical truth which is so startling; that makes us wonder whether, in this all-important matter, Greek artistry could possibly have been anticipated by the sculptors of a far-off age on the banks of the Indus.
Many crafts “such as shell working, ceramics, and agate and glazed steatite bead making” were used in the making of necklaces, bangles, and other ornaments from all phases of Harappan sites and some of these crafts are still practised in the subcontinent today. Some make-up and toiletry items (a special kind of combs (kakai), the use of collyrium and a special three-in-one toiletry gadget) that were found in Harappan contexts still have similar counterparts in modern India. Terracotta female figurines were found (ca. 2800-2600 BCE) which had red colour applied to the “manga” (line of partition of the hair).
Seals have been found at Mohenjo-Daro depicting a figure standing on its head, and another sitting cross-legged in what some call a yoga-like pose (see image, the so-called Pashupati, below).
This figure, sometimes known as a Pashupati, has been variously identified. Sir John Marshall identified a resemblance to the Hindu god, Shiva. If this can be validated, it would be evidence that some aspects of Hinduism predate the earliest texts, the Veda.
A harp-like instrument depicted on an Indus seal and two shell objects found at Lothal indicate the use of stringed musical instruments. The Harappans also made various toys and games, among them cubical dice (with one to six holes on the faces), which were found in sites like Mohenjo-Daro.
Trade and transportation(Indus Valley Civilization)
The Indus civilization’s economy appears to have depended significantly on trade, which was facilitated by major advances in transport technology. The IVC may have been the first civililzation to use wheeled transport. These advances may have included bullock carts that are identical to those seen throughout South Asia today, as well as boats. Most of these boats were probably small, flat-bottomed craft, perhaps driven by sail, similar to those one can see on the Indus River today; however, there is secondary evidence of sea-going craft. Archaeologists have discovered a massive, dredged canal and what they regard as a docking facility at the coastal city of Lothal in western India (Gujarat state). An extensive canal network, used for irrigation, has however also been discovered by H.-P. Francfort.
During 4300–3200 BCE of the chalcolithic period (copper age), the Indus Valley Civilization area shows ceramic similarities with southern Turkmenistan and northern Iran which suggest considerable mobility and trade. During the Early Harappan period (about 3200–2600 BCE), similarities in pottery, seals, figurines, ornaments, etc. document intensive caravan trade with Central Asia and the Iranian plateau.
Judging from the dispersal of Indus civilisation artifacts, the trade networks, economically, integrated a huge area, including portions of Afghanistan, the coastal regions of Persia, northern and western India, and Mesopotamia.
There is some evidence that trade contacts extended to Crete and possibly to Egypt.
There was an extensive maritime trade network operating between the Harappan and Mesopotamian civilizations as early as the middle Harappan Phase, with much commerce being handled by “middlemen merchants from Dilmun” (modern Bahrain and Failaka located in the Persian Gulf).Such long-distance sea trade became feasible with the innovative development of plank-built watercraft, equipped with a single central mast supporting a sail of woven rushes or cloth.
Several coastal settlements like Sotkagen-dor (astride Dasht River, north of Jiwani), Sokhta Koh (astride Shadi River, north of Pasni), and Balakot (near Sonmiani) in Pakistan along with Lothal in India testify to their role as Harappan trading outposts. Shallow harbors located at the estuaries of rivers opening into the sea allowed brisk maritime trade with Mesopotamian cities.
Ten Indus Scripts, dubbed “Signboard”, Dholavira
Typical Indus inscriptions are no more than four or five characters in length, most of which (aside from the Dholavira “signboard”) are tiny; the longest on a single surface, which is less than 1 inch (2.54 cm) square, is 17 signs long; the longest on any object (found on three different faces of a mass-produced object) has a length of 26 symbols.
While the Indus Valley Civilization is generally characterized as a literate society on the evidence of these inscriptions, this description has been challenged by Farmer, Sproat, and Witzel (2004)who argue that the Indus system did not encode language, but was instead similar to a variety of non-linguistic sign systems used extensively in the Near East and other societies. Others have claimed on occasion that the symbols were exclusively used for economic transactions, but this claim leaves unexplained the appearance of Indus symbols on many ritual objects, many of which were mass-produced in moulds. No parallels to these mass-produced inscriptions are known in any other early ancient civilizations.
In a 2009 study by P. N. Rao et al. published in Science, computer scientists, comparing the pattern of symbols to various linguistic scripts and non-linguistic systems, including DNA and a computer programming language, found that the Indus script’s pattern is closer to that of spoken words, supporting the hypothesis that it codes for an as-yet-unknown language.
Farmer, Sproat, and Witzel have disputed this finding, pointing out that Rao et al. did not actually compare the Indus signs with “real-world non-linguistic systems” but rather with “two wholly artificial systems invented by the authors, one consisting of 200,000 randomly ordered signs and another of 200,000 fully ordered signs, that they spuriously claim represent the structures of all real-world non-linguistic sign systems”. Farmer et al. have also demonstrated that a comparison of a non-linguistic system like medieval heraldic signs with natural languages yields results similar to those that Rao et al. obtained with Indus signs. They conclude that the method used by Rao et al. cannot distinguish linguistic systems from non-linguistic ones.
The messages on the seals have proved to be too short to be decoded by a computer. Each seal has a distinctive combination of symbols and there are too few examples of each sequence to provide a sufficient context. The symbols that accompany the images vary from seal to seal, making it impossible to derive a meaning for the symbols from the images. There have, nonetheless, been a number of interpretations offered for the meaning of the seals. These interpretations have been marked by ambiguity and subjectivity.
Photos of many of the thousands of extant inscriptions are published in the Corpus of Indus Seals and Inscriptions (1987, 1991, 2010), edited by Asko Parpola and his colleagues. The final, third, volume, republished photos taken in the 1920s and 1930s of hundreds of lost or stolen inscriptions, along with many discovered in the last few decades. Formerly, researchers had to supplement the materials in the Corpus by study of the tiny photos in the excavation reports of Marshall (1931), MacKay (1938, 1943), Wheeler (1947), or reproductions in more recent scattered sources.
Some Indus valley seals show swastikas, which are found in other religions (worldwide), especially in Indian religions such as Hinduism,Buddhism, and Jainism. The earliest evidence for elements of Hinduism are alleged to have been present before and during the early Harappan period. Phallic symbols interpreted as the much later Hindu Shiva lingam have been found in the Harappan remains.
Many Indus valley seals show animals. One motif shows a horned figure seated in a posture reminiscent of the Lotus position and surrounded by animals was named by early excavators Pashupati (lord of cattle), an epithet of the later Hindu gods Shiva andRudra.
In view of the large number of figurines found in the Indus valley, some scholars believe that the Harappan people worshipped a Mother goddess symbolizing fertility, a common practice among rural Hindus even today. However, this view has been disputed by S. Clark who sees it as an inadequate explanation of the function and construction of many of the figurines.
There are no religious buildings or evidence of elaborate burials. If there were temples, they have not been identified. However, House – 1 in HR-A area in Mohenjadaro’s Lower Town has been identified as a possible temple.
In the earlier phases of their culture, the Harappans buried their dead; however, later, especially in the Cemetery H culture of the late Harrapan period, they also cremated their dead and buried the ashes in burial urns.
It is possible that a temple exists to the East of the great bath, but the site has not been excavated. There is a Buddhist reliquary mound on the site and permission has not been granted to move it. Until there is sufficient evidence, speculation about the religion of the IVC is largely based on a retrospective view from a much later Hindu perspective.
Ram Prasad Chanda, who supervised Indus Valley Civilisation excavations, states that, “Not only the seated deities on some of the Indus seals are in Yoga posture and bear witness to the prevalence of Yoga in the Indus Valley Civilisation in that remote age, the standing deities on the seals also show Kayotsarga (a standing or sitting posture of meditation) position. The Kayotsarga posture is peculiarly Jain. It is a posture not of sitting but of standing. In the Adi Purana Book XV III, the Kayotsarga posture is described in connection with the penance ofRsabha, also known as Vrsabha.”
Christopher Key Chappel also notes some other possible links with Jainism. Seal 420, unearthed at Mohenjodaro portrays a person with 3 or possibly 4 faces. Jain iconography frequently depicts its Tirthankaras with four faces, symbolizing their presence in all four directions. This four-faced attribute is also true of many Hindu gods, important among them being Brahma, the chief creator deity. In addition, Depictions of a bull appear repeatedly in the artifacts of the Indus Valley. Lannoy, Thomas McEvilley and Padmanabh Jainihave all suggested that the abundant use of the bull image in the Indus Valley civilization indicates a link with Rsabha, whose companion animal is the bull. This seal can be interpreted in many ways, and authors such as Christopher Key Chappel and Richard Lannoy support the Jain interpretation.
The collapse and Late Harappan
Around 1800 BCE, signs of a gradual decline began to emerge, and by around 1700 BCE, most of the cities were abandoned. In 1953, Sir Mortimer Wheeler proposed that the decline of the Indus Civilization was caused by the invasion of an Indo-European tribe from Central Asia called the “Aryans”. As evidence, he cited a group of 37 skeletons found in various parts of Mohenjo-Daro, and passages in the Vedas referring to battles and forts. However, scholars soon started to reject Wheeler’s theory, since the skeletons belonged to a period after the city’s abandonment and none were found near the citadel. Subsequent examinations of the skeletons by Kenneth Kennedy in 1994 showed that the marks on the skulls were caused by erosion, and not violent aggression. Today, many scholars believe that the collapse of the Indus Civilization was caused by drought and a decline in trade with Egypt and Mesopotamia. It has also been suggested that immigration by new peoples, deforestation, floods, or changes in the course of the river may have contributed to the collapse of the IVC.
Previously, it was also believed that the decline of the Harappan civilization led to an interruption of urban life in the Indian subcontinent. However, the Indus Valley Civilization did not disappear suddenly, and many elements of the Indus Civilization can be found in later cultures. Current archaeological data suggest that material culture classified as Late Harappan may have persisted until at least c. 1000-900 BCE and was partially contemporaneous with the Painted Grey Ware culture. Harvard archaeologist Richard Meadow points to the late Harappan settlement of Pirak, which thrived continuously from 1800 BCE to the time of the invasion of Alexander the Great in 325 BCE.
Recent archaeological excavations indicate that the decline of Harappa drove people eastward. After 1900 BCE, the number of sites in India increased from 218 to 853. Excavations in the Gangetic plain show that urban settlement began around 1200 BCE, only a few centuries after the decline of Harappa and much earlier than previously expected.Archaeologists have emphasized that, just as in most areas of the world, there was a continuous series of cultural developments. These link “the so-called two major phases of urbanization in South Asia”.
A possible natural reason for the IVC’s decline is connected with climate change that is also signalled for the neighbouring areas of the Middle East: The Indus valley climate grew significantly cooler and drier from about 1800 BCE, linked to a general weakening of the monsoon at that time. Alternatively, a crucial factor may have been the disappearance of substantial portions of the Ghaggar Hakra river system. A tectonic event may have diverted the system’s sources toward the Ganges Plain, though there is complete uncertainty about the date of this event, as most settlements inside Ghaggar-Hakra river beds have not yet been dated. The actual reason for decline might be any combination of these factors. New geological research is now being conducted by a group led by Peter Clift, from the University of Aberdeen, to investigate how the courses of rivers have changed in this region since 8000 years ago, to test whether climate or river reorganizations are responsible for the decline of the Harappan. A 2004 paper indicated that the isotopes of the Ghaggar-Hakra system do not come from the Himalayan glaciers, and were rain-fed instead, contradicting a Harappan time mighty “Sarasvati” river.
A research team led by the geologist Liviu Giosan of the Woods Hole Oceanographic Institution also concluded that climate change in form of the easterward migration of the monsoons led to the decline of the IVC. The team’s findings were published in PNAS in May 2012. According to their theory, the slow eastward migration of the monsoons across Asia initially allowed the civilization to develop. The monsoon-supported farming led to large agricultural surpluses, which in turn supported the development of cities. The IVC residents did not develop irrigation capabilities, relying mainly on the seasonal monsoons. As the monsoons kept shifting eastward, the water supply for the agricultural activities dried up. The residents then migrated towards the Ganges basin in the east, where they established smaller villages and isolated farms. The small surplus produced in these small communities did not allow development of trade, and the cities died out.
Historical context and linguistic affiliation
After the discovery of the IVC in the 1920s, it was immediately associated with the indigenous Dasyu inimical to the Rigvedic tribes in numerous hymns of the Rigveda. Mortimer Wheeler interpreted the presence of many unburied corpses found in the top levels of Mohenjo-Daro as the victims of a warlike conquest, and famously stated that “Indra stands accused” of the destruction of the IVC. The association of the IVC with the city-dwelling Dasyus remains alluring because the assumed timeframe of the first Indo-Aryan migrationinto India corresponds neatly with the period of decline of the IVC seen in the archaeological record. The discovery of the advanced, urban IVC however changed the 19th century view of early Indo-Aryan migration as an “invasion” of an advanced culture at the expense of a “primitive” aboriginal population to a gradual acculturation of nomadic “barbarians” on an advanced urban civilization, comparable to the Germanic migrations after the Fall of Rome, or the Kassite invasion of Babylonia. This move away from simplistic “invasionist” scenarios parallels similar developments in thinking about language transfer and population movement in general, such as in the case of the migration of the proto-Greek speakers into Greece, or the Indo-Europeanization of Western Europe.
It was often suggested that the bearers of the IVC corresponded to proto-Dravidians linguistically, the breakup of proto-Dravidian corresponding to the breakup of the Late Harappanculture. Today, the Dravidian language family is concentrated mostly in southern India and northern Sri Lanka, but pockets of it still remain throughout the rest of India and Pakistan (the Brahui language), which lends credence to the theory. Finnish Indologist Asko Parpola concludes that the uniformity of the Indus inscriptions precludes any possibility of widely different languages being used, and that an early form of Dravidian language must have been the language of the Indus people. However, in an interview with the Deccan Herald on August 12, 2012, Asko Parpola clarified his position by admitting that Sanskrit-speakers had contributed to the Indus Valley Civilization. Proto-Munda (or Para-Munda) and a “lost phylum” (perhaps related or ancestral to the Nihali language) have been proposed as other candidates.
The civilization is sometimes referred to as the Indus Ghaggar-Hakra civilization or the Indus-Sarasvati civilization by Hindutva groups, which is based on theories of Indigenous Aryans and the Out of India migration of Indo-European speakers.