Indus Valley Civilisation

The Indus or Harappan civilisation (mature phase c. 2600-1900 BCE) was the subcontinent's first urban civilisation, spread over roughly 1.3 million square kilometres across present-day Pakistan, north-west India and Afghanistan. Its signature features are town planning on a grid, standardised burnt bricks, drainage, weights, and an undeciphered script.

Discovery, phases and extent

Harappa was excavated by Daya Ram Sahni in 1921 and Mohenjodaro by R. D. Banerji in 1922, both under John Marshall as Director General of the Archaeological Survey of India. Because the script cannot be read, the civilisation is classed as protohistoric.

The four boundary sites are worth memorising as a set: Sutkagendor in the west (Balochistan), Alamgirpur in the east (Uttar Pradesh), Manda in the north (Jammu, on the Chenab) and Daimabad in the south (Maharashtra, on the Pravara). Present-day India holds the largest number of sites, with Rakhigarhi in Haryana the biggest Indian site.

Town planning and architecture

The typical mature Harappan city has two mounds - a raised citadel to the west with public structures, and a lower town to the east with residential blocks. Streets cut each other at right angles in a grid, houses open onto side lanes rather than the main street, and every house has a bathroom connected to a covered street drain. Baked bricks are used in a fixed ratio, which is itself a sign of central standardisation.

Harappan brick ratio = 1 : 2 : 4 (thickness : width : length)

Economy, society and religion

The economy rested on agriculture (wheat, barley, cotton - the Greeks called cotton sindon after Sindh - and rice only at Lothal and Rangpur), craft production and trade. Trade with Mesopotamia is confirmed by Harappan seals found there and by Mesopotamian references to Meluha, generally identified with the Indus region. Weights follow a binary then decimal system in multiples of 16. No coins were used - trade was by barter.

• Seals are mostly steatite, square, with an animal and a short inscription; the unicorn is the commonest motif
• Script is pictographic, written boustrophedon - right to left in the first line, then left to right
• No temple has been identified with certainty; religion is inferred from seals and figurines
• Mother Goddess terracotta figurines, the Pashupati seal, and worship of the pipal tree and humped bull
• Burials are generally north-south extended; Kalibangan shows symbolic burials, Lothal a few paired burials

✗ The Harappans knew iron and used coins  |  ✓ The Harappans used copper and bronze; iron and coins were unknown

Decline

No single explanation is accepted. The main hypotheses are climate change and increasing aridity, the drying or shifting of the Ghaggar-Hakra river system, tectonic activity and flooding (Mohenjodaro shows repeated flood layers), deforestation and ecological stress from brick firing, and the breakdown of trade with Mesopotamia. The Aryan invasion theory of Mortimer Wheeler, based on unburied skeletons at Mohenjodaro, is now largely rejected. What actually happened was de-urbanisation rather than extinction - Late Harappan villages continue eastwards.

FAQ

Why is the Indus civilisation called protohistoric?

Because the Harappans had writing but the script has not been deciphered. Prehistory means no writing at all; history means readable records. The Harappan script, with about 400 signs written boustrophedon, remains unread, so the period sits between the two.

Which Harappan sites are in India today?

Rakhigarhi, Banawali and Bhirrana in Haryana, Kalibangan in Rajasthan, Lothal, Dholavira, Surkotada and Rangpur in Gujarat, Alamgirpur in Uttar Pradesh, Manda in Jammu and Daimabad in Maharashtra. India has more excavated Harappan sites than Pakistan.

What does the Great Bath tell us about Harappan society?

The Great Bath at Mohenjodaro, about 12 by 7 metres with a bitumen lining and side rooms, points to organised public works and probably to ritual bathing. It shows both engineering skill in waterproofing and a civic authority able to build and maintain shared facilities.