Question

how did the Harappan Civilization decline?

Answer 1

Proposed theories regarding the decline of the Harappan Civilization

Definite reason that led to the decline of the Indus Valley Civilization is not known, as no reliable resource of that period is available at present. Every conclusion regarding the decline is based upon speculations of historians. Though the reason of the decline is not known, but through excavations it is clear that fall of the Harappan Civilization occurred between 1800 BC to 1700 BC.

It is commonly believed that the Aryans were the next settlers. They were skilled fighters, so their attack might have led to the destruction of the Harappan Civilization. Even the epics of the Aryans mentioned about their victory over the great cities. The human remains found during excavation of Indus valley point towards some violent cause of their death. Now many historians, who do not believe this theory, say that the Aryans might not be involved in any such attack.

Owing to this conflict, the theory of a huge climatic change or natural disaster gained credibility. It has been found out that around 2000 BC some major climatic changes started occurring in the Indus Valley. These changes had led to floods in the plains and cities. Historians have found evidence to prove this theory as well. Most of the cities in the Harappan Civilization have been found in a condition as if these had been first abandoned

Answer 2

hai friend here is your answer
It is said that invasion of Aryans was one of the reason for decline in Indus Vallley Civilisation because 1500 BCEHarappan/Indus Valley Civilisationcame to end and 1500 BCE marks the beginning of Aryans. Originally Answered: Why is the Indus Valleydestroyed? This civilization is said to have come to an abrupt end.
hope it helps you