Harappan Civilization: Decline Of The Indus Valley Civilization


The Harappan civilization, also known as the Indus Valley civilization, was one of the earliest urban civilizations in the world, with a history that spans from approximately 2600 BCE to 1900 BCE. The civilization was spread across a vast area that included parts of modern-day India, Pakistan, and Afghanistan, and was characterized by advanced urban planning, impressive architecture, and a sophisticated system of writing and trade.

Despite its remarkable achievements, the Harappan civilization eventually declined and disappeared, leaving behind a legacy that continues to fascinate historians and archaeologists to this day. The reasons for this decline are still a subject of much debate, but scholars believe that a combination of factors, including environmental changes, natural disasters, and invasions from neighboring tribes, played a role in the collapse of this ancient civilization.

According to JOHN MARSHALL, the change in the course of Indus caused floods which wiped out the civilisation. however floods were seen only at mohenjo daro and Chaudhari That's why this view was not widely accepted.

MORTIMER WHEELER : According to him people were massacred on the streets. He give the example of a room where 13 men and women skeletons were found with dagger wounds. he believed that aryans invaded the civilisation However! this view was not accepted because few skeletons were found with dagger wounds which shows that they died due to diseases Also there is no culture following indus valley civilization , There was a a gap of 500 to 1000 years.

According to ROMILA THAPAR, the decline was explained by multiple causes but they don't have universal application. In some areas they were reverse pattern some people migrated from countryside to cities & cities to rural areas resulting in ruralification.

some people migrated away from the ghaggar region away from the gujarat to maharashtra north western region faced invasions from Aryans she mentioned that decline does not mean complete cultural disappearance only the urban function stopped working and some overlapping features were seen in the next civilization.

after WHEELER , the views were given by RAFIQ MUGHAL , KENNETH KENNEDY they held environmental factors such as change in course of river and climate resulted in non-accessibility of natural resources. excessive deforestation and overgrazing resulted in soil erosion , increasing soil salinity and making area unsuitable for cultivation. forest were destroyed to make axes 20 axes would require 700 KG of wood .so Forests were destroyed on a large scale.

D.N. JHA urban decay sit much before the actual decline A large number of cities became slums structures like great bath and granaries fell into disuse average settlement size fell from 85 Hectares to 3 Hectares this decay was accompanased by vanishing of tools , weights and measures. People migrated to other areas . In mohanjodaro due to floods , people migrated towards punjab , haryana and U.P. there were attacks in the north western region . In Baluchistan , there is a thick layer of burning , which imply there was destruction due to burning. some alien culture was super imposed on the Harappan culture as skeletons were found in symmetries in large number.


Between 3300 to 1300 BCE, the Harappan Civilization, which is also referred to as the Indus River Valley Civilization, flourished across present-day northeast Afghanistan, Pakistan, and northwest India. The decline of this ancient civilization, which occurred around 1800 BCE, remains a topic of discussion among scholars. While some theories propose natural disasters and environmental changes as the cause, others suggest invasion by the Aryans, a nomadic Indo-European group, as a contributing factor to the collapse of the Indus Valley Civilization.


Around 1800 BCE, there is evidence to suggest that many of the major Mature Harappan sites, particularly in regions like Cholistan, had been abandoned, while there was a concurrent increase in population in new settlements in Gujarat, Haryana, and western Uttar Pradesh. The cause of the decline of the Harappan Civilization is a subject of academic debate, with many scholars proposing environmental change as a contributing factor.

Some scholars argue that the region's climate changed due to the drying up of the Saraswati River around 1900 BCE, while others suggest a significant flood occurred during this time. The abrupt collapse of the Indus Civilization was not due to an invasion, as various elements of the civilization have been discovered in later societies. Instead, many researchers suggest that the dissolution of the large civilization into smaller communities, known as the late Harappan civilizations, was triggered by changes in river patterns.


The decline of the Harappan Civilization has been attributed to a variety of factors, including the mismanagement of the landscape, deforestation, climate change, severe flooding, waterway shifting or drying up, and extreme weather conditions. While these explanations may be valid for specific regions, they do not fully account for the civilization's collapse as a whole. Another potential cause of climatic changes in the Harappan region may have been the eastward-blowing winds that generate heavy rain during the monsoon season, which can have either beneficial or detrimental effects on flora and crops.

By 1800 BCE, the Indus Valley had become colder and drier, and the river networks that had supported the Harappan Civilization may have been disrupted or rerouted due to seismic events. As a result, the Harappans may have migrated to the Ganges basin, where they founded villages and solitary farms that could not produce the agricultural surpluses required to support larger communities. This led to a decline in trade with Egypt and Mesopotamia, as the production of goods decreased. By 1700 BCE, most of the cities of the Indus Valley Civilization had been abandoned.


The decline of the Harappan Civilization has been associated with various theories. Monsoons, which can either support or destroy flora and crops depending on their intensity, have been considered a factor. By 1800 BCE, the Indus Valley had become colder and drier, and the river networks that had sustained the Harappan Civilization may have been disrupted or rerouted due to seismic activity. The Harappans may have migrated to the Ganges basin, where they established small towns, villages, and solitary farms.

However, these smaller settlements were unable to produce the agricultural surpluses required to sustain larger communities, resulting in reduced production and trade with Egypt and Mesopotamia. By approximately 1700 BCE, most of the cities in the Indus Valley Civilization had been abandoned.


The theory that the Harappan Civilization was destroyed by an Aryan invasion was first proposed by Ramaprasad Chanda, but later popularized by Mortimer Wheeler. Wheeler suggested that the Harappan civilization was completely wiped out by the Aryan invasion, citing human skeletons discovered at Mohenjodaro during the final phases of occupation as evidence of an Aryan massacre.

Wheeler argued that various references to different types of forts, attacks on fortified towns, and the god Indra's title purandara (meaning fort destroyer) all pointed to an Aryan invasion of the Harappan cities. The Rig Vedic Aryans inhabited Punjab and the Ghaggar-Hakra region, and Wheeler believed that the Harappan cities were being mentioned in the Rig Veda as no other cultural groups had forts in this area at that time.

However, the theory of Aryan invasion is now contested by many scholars, who argue that there is no conclusive evidence to support this idea. It is now believed that the Harappan Civilization may have declined due to various factors such as climate change, seismic activity, and migration to new areas, rather than being wiped out by invaders.


Natural disasters, although not always immediate or isolated, may have played a role in the decline of the Harappan civilization. The presence of silt deposits in numerous Indus cities, such as Mohenjodaro, Chanhudaro, and Lothal, suggests that destruction caused by swollen rivers was possible. In the case of Mohenjodaro, several layers of silt indicate that the city was affected by multiple floods, leading to the disintegration of the Harappan civilization.

Evidence of major flooding is indicated by the accumulation of crumbled building materials and silty clay on Mohenjodaro’s homes and streets, with the silty mud believed to have been deposited by floodwaters that inundated the city. After the floods receded, the inhabitants rebuilt their homes and streets on top of the remains of the previous buildings. At least three instances of this catastrophic flooding and subsequent reconstruction are believed to have taken place.

Some scholars, including M.R. Sahni, George F. Dales, and Robert L. Raikes, have proposed that human errors may have contributed to the floods at Mohenjodaro, while others believe that tectonic changes may have played a role. One theory is that the Indus region is seismically active, and tectonic movements caused a massive natural barrier to form, preventing the Indus from flowing towards the sea and creating a large lagoon in the area around Mohenjodaro.


According to scholars such as Fairservis, the decline of the Harappan civilization was caused by an ecological imbalance. Fairservis analyzed current data on population, land, food, and fodder requirements, and hypothesized that the resources available in the Harappan cultural zone were not enough to support the increasing population and cattle. The semi-arid regions were fragile and human and cattle populations quickly depleted the few trees, food, and fuel sources, leading to a disturbance of the ecological balance. The Harappans exploited the environment excessively, cutting down trees for farming and fuel and practicing over-cultivation, over-grazing, and over-farming. However, the production capacity of the communities was not enough to meet the needs of the growing human and animal population, leading to degradation of the landscape. Consequently, the forests and grasslands gradually disappeared, and this led to an increase in flooding, droughts, and soil salinity. In summary, the ecological imbalance caused by the Harappans' excessive exploitation of the environment led to the decline of the Harappan civilization.


Lambrick suggested that changes in the course of the Indus River might have played a role in the decline of the Indus Valley civilization. The Indus River is an intricate network of waterways with an unstable bed, and it reportedly shifted away from Mohenjodaro by about thirty kilometers. Due to the lack of water, the city's inhabitants and the surrounding agrarian villages had to migrate several times.

This phenomenon happened many times during Mohenjodaro's existence. The wind brought a significant amount of sand and silt into the city, resulting in the visible silt. Due to the combination of this silt with crumbling mud, mud brick, and baked brick buildings, it was often mistaken for river silt.


While natural floods may have contributed to the erosion of Mohenjodaro, Harappan sites in the Ghaggar-Hakra region faced progressive desiccation. According to D.P. Agarwal and Sood, the Harappan civilization perished when the Ghaggar-Hakra river dried up, and the area became more arid. They discovered that the amount of dry weather had increased by the middle of the second millennium B.C. In semi-arid regions like Harappa, even a minor reduction in moisture and water supply could have catastrophic effects on agricultural output, which would put a strain on cities' economies.


In conclusion, the decline of the Harappan civilization remains a topic of great interest and debate among scholars. While there are several theories and factors that could have contributed to its collapse, the ecological imbalance, natural disasters, and climate change seem to have played a significant role. The over-exploitation of resources, unsustainable land use practices, and deforestation by the Harappans contributed to ecological degradation, leading to soil salinity, floods, and droughts. Additionally, changes in the Indus River's course and the drying up of the Ghaggar-Hakra waterway led to a lack of water supply and agricultural output, further straining the economy of the Harappan cities. Ultimately, the Harappan civilization's collapse serves as a lesson on the importance of sustainable land use practices and ecological balance to ensure the long-term survival of civilizations.