This chapter covers India before written history: the Palaeolithic, Mesolithic and Neolithic stages, the copper-using Chalcolithic villages, and the first Indian cities of the Harappan (Indus Valley) Civilisation.

What UPSC asks

Prelims is site-heavy: which site lies on which river or in which State, what was found where (a ploughed field, a dockyard, pit dwellings, rock paintings), and which features the Harappans did not have (iron, a deciphered script, a confirmed horse).
Mains GS I asks through culture: Harappan town planning, art (bronze casting, seals, terracotta), continuity of Harappan traits in later Indian life, and the debate on why the cities declined.

Key sub-topics

Sub-topic	Focus
Stone Age cultures	Tool types, Bhimbetka rock art, Mehrgarh and the first farmers
Chalcolithic cultures	Ahar-Banas, Malwa, Jorwe; village life with copper
Harappan Civilisation	Phases, sites and rivers, town planning, economy, seals, religion
Decline	Climate, rivers, trade — and why the “invasion” theory was abandoned

Start with The Harappan Civilisation, then Stone Age and Chalcolithic Cultures, and test yourself on the practice questions.