Indus Valley

About 3000 BC, a great civilization grew up along the river Indus in the Indian subcontinent (in what is now Pakistan). It is known as the Indus Valley civilization. About 2500 BC, it reached the height of its power.

The Indus Valley civilization was larger than either Sumer or ancient Egypt. Its two great cities were Harappa and Mohenjo Daro, each with a population of some 40,000 people.

The civilization had a highly organized system of trade. Merchants traded grain and other agricultural produce, grown on the fertile river plains. Artefacts and jewellery were also traded for precious metals and cloth. From about 2000 BC, however, this mighty civilization began to decline, possibly because terrible floods destroyed the crops, or because the river Indus changed course and the fertile farmland dried up. Another theory is that over-grazing left the land too dry and poor to support crops.