Indus Valley Civilization — TNPSC Group 4 History Notes

Overview

The Indus Valley Civilization (2600–1900 BC) was one of the world's earliest urban civilizations, flourishing in the northwestern part of the Indian subcontinent — present-day Pakistan and northwest India. It developed alongside the Mesopotamian and Egyptian civilizations, making it part of the ancient world's first great urban revolution. The civilization is also known as the Harappan Civilization because Harappa was the first site to be excavated and formally identified.

John Marshall of the Archaeological Survey of India announced the discovery to the world in 1921. The civilization's advanced urban planning, sophisticated drainage system, and standardized weights left scholars astonished at the level of civic organization achieved nearly 5,000 years ago.

Major Sites and Their Features

The civilization extended over an area larger than ancient Egypt or Mesopotamia.

Town Planning and Urban Features

The cities were laid out on a grid pattern — streets crossing at right angles. Two main sections existed in every major city: a citadel (elevated fortified area for public buildings) and a lower town (residential area for the general population).

The most remarkable achievement was the underground drainage system. Every house had drains connected to covered street drains, demonstrating a level of civic sanitation not seen again until modern times. Houses were built of standardized baked bricks (ratio 1:2:4), indicating centralized planning and quality control.

The Great Bath at Mohenjo-daro was a large rectangular water tank measuring 12 m × 7 m, waterproofed with bitumen. It is believed to have been used for ritual bathing.

Trade, Economy, and Society

The Harappan people engaged in long-distance trade with Mesopotamia (present-day Iraq), exchanging cotton textiles, beads, and ivory for metals and other goods. Mesopotamian texts refer to trade with a place called "Meluhha," believed to be the Indus region.

They used standardized weights and measures — a decimal system for weighing goods, which facilitated fair trade. The dockyard at Lothal shows that they had maritime trade capabilities.

Agriculture was the primary occupation. They grew wheat, barley, sesame, and, most importantly, cotton — the Harappans were the world's first to cultivate and weave cotton.

The Undeciphered Script

The Indus script consisted of approximately 400 signs written on small seals made of steatite (soapstone). The script has not been deciphered despite decades of effort. It appears to be written from right to left. The most common motif on seals is the unicorn, followed by the humpless bull and elephant.

Decline of the Civilization

By 1900 BC, the major cities were abandoned. The reasons are still debated among scholars:

• Climate change and drought — most likely cause, supported by modern geological evidence
• Floods from the Indus River
• Aryan invasion — now largely discredited by most historians
• Epidemic or disease
• Shifting of rivers — the drying up of the Ghaggar-Hakra (possibly the Vedic Saraswati) river system

Important for Exam - Great Bath is at Mohenjo-daro - Ancient dockyard is at Lothal (Gujarat) - First to cultivate cotton in the world - Script is still undeciphered - Cities used standardized bricks in 1:2:4 ratio - Announced by John Marshall in 1921