Indus Valley Civilisation: Sites, Town Planning and Decline

The Indus Valley Civilisation, also called the Harappan Civilisation, is the earliest urban civilisation of the Indian subcontinent and one of the three great Bronze Age civilisations of the ancient world, alongside Mesopotamia and Egypt. Examiners return to it every year because its facts are fixed and easy to test: which site gave which find, which river a city stood on, who excavated it and in which year. This note gives those facts in the order an exam asks for them.

Discovery, date and extent

The civilisation is named after Harappa, the first of its sites to be excavated. Daya Ram Sahni excavated Harappa in 1921 and R. D. Banerji reached Mohenjo-daro in 1922. Both worked under Sir John Marshall, then Director General of the Archaeological Survey of India, who announced the discovery to the world in 1924. The mature urban phase of the civilisation is placed between about 2600 BCE and 1900 BCE, with an early Harappan phase before it and a late, declining phase after it.

In area it was the largest of the Bronze Age civilisations. Its known limits are Sutkagendor in the west, on the Makran coast of Baluchistan; Alamgirpur in the east, on the Hindon in Uttar Pradesh; Manda in the north, on the Chenab in Jammu; and Daimabad in the south, on the Pravara in Maharashtra. Joined up, these outer sites form a rough triangle of well over a million square kilometres spread across present-day Pakistan and north-western India. The civilisation belongs to the Bronze Age: its people used copper, bronze, gold and silver, but knew no iron.

Major sites and what was found there

Town planning and drainage

The planning is the most examined feature of the civilisation, because it was the same in city after city.

• Towns were laid out on a grid, with streets crossing one another at right angles and dividing the settlement into rectangular blocks.
• A typical town had two parts: a raised citadel to the west, holding the public buildings, and a larger lower town to the east where people lived.
• Houses were built of burnt bricks of a fixed ratio of 4:2:1 in length, breadth and thickness, an early example of standardisation.
• Every street had a covered drain of brick with manholes at intervals for cleaning, and house drains fed into it. No other ancient civilisation matched this drainage system.
• The Great Bath at Mohenjo-daro, about twelve metres long and seven metres wide, was made watertight with a layer of natural tar, and was probably used for ritual bathing.
• The largest building at Mohenjo-daro is the Great Granary; Harappa has granaries close to its citadel.

Farming, crafts and trade

The Harappans grew wheat, barley, peas, sesame and mustard; rice husk has been found at Lothal and Rangpur in Gujarat. They were the first people in the world to grow cotton, which later Greeks called Sindon after the Indus. They kept humped cattle, buffaloes, sheep, goats, pigs and dogs, and knew the elephant and the camel; the horse is not an established part of Harappan life. Trade was carried on by barter, since no coins have been found, and weights and measures ran in multiples of sixteen. Sea and land trade linked the Harappans to Mesopotamia, whose records call the Indus region Meluha; Dilmun, identified with Bahrain, and Magan, identified with Oman, lay on the route. Lapis lazuli came from Afghanistan and the Harappan outpost of Shortughai, copper from Khetri in Rajasthan and gold from the Kolar region in the south.

Seals, script and religion

Seals, usually square and cut in steatite, are the signature object of the civilisation. The unicorn is the commonest figure on them; the best known is the Pashupati seal from Mohenjo-daro, showing a three-faced figure seated among animals, taken by many scholars as a proto-Shiva. The script is pictographic, has around four hundred signs, was written from right to left in the first line and left to right in the next, and remains undeciphered, which is why the civilisation counts as proto-historic. No temple has been identified. The people worshipped a mother goddess, the pipal tree and the humped bull, and buried their dead, usually extended and laid north to south.

Decline of the civilisation

The cities were abandoned by about 1900 BCE, and no single cause is accepted. Mortimer Wheeler argued for an Aryan invasion, reading the skeletons of Mohenjo-daro as evidence of a massacre, an explanation now largely rejected. John Marshall and Ernest Mackay pointed to repeated floods, and S. R. Rao to the same at Lothal. Others propose tectonic movement that dammed the rivers, the drying up of the Ghaggar-Hakra, growing aridity, deforestation caused by the enormous demand for fuel to bake bricks, and the failure of trade with Mesopotamia. Most historians now treat the end as a gradual decline in which climate and the shifting of rivers did the greater part.