Answer:

The Harappan culture flourished about 1800 BC. Afterwards, the culture began to decline. Many mature Harappan sites in regions such Cholistan were abandoned by the 1800 BC. Population expanded in new settlements in Gujarat, Haryana and WESTERN Uttar Pradesh.

There is no unanimity among HISTORIANS on the exact reason of the decline of

this civilization. Different scholars have put different theories of decline of this civilization forward. The FOLLOWING table gives the important theories and their profounder regarding the decline of Harappan Civilisation.

Different Opinions about the Decline of Harappan Civilisation

Thinkers

Opinion

↗Stuart, Piggott and Gordon-Childe

External aggression (Aryan invasion)

↗MR Sahni

Inundation

↗KVR Kennedy

Epidemic

↗Marshall and Raikes

Tectonic disturbances

↗Aurel Strein and AN Ghosh

Climate Change

↗Walter Fairservis

Deforestation, scarcity of resources, ecological imbalances

↗Marshal, SR Rao, Maickey

Flood

↗GF Hales

The destruction due to change in the COURSE of river Ghaggar.

↗Wheeler

In his Ancient Indiamentioned that the climatic, economic and political civilisation and argued that the decline was actually due to a large-scale destruction.

↗George Dales

In his ‘The Mythical Massacre at Mohenjo-Daro’refuted Wheeler’s Theory of Invasion and argues that the skeletons found did not belong to the Harappan period and were burials of irreverent nature.

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