Question

what was the main reason for the downfall of harappan civilization?

Answer 1

Due to change in the climatic condition, the area lost fertil­ity and people were compelled to move else where.

Constant use of firewood for brick manufacture caused deforestation and minimized the rainfall.

The change of course of the river Indus transformed it into a tract of sand and affected the fertility.

Natural calamities like earthquake and cyclones adversely affected the normal life.

Some scholars are of opinion that the Harappan civilization suffered a decline due to attacks by the hostile tribes and the Aryans. M. Wheeler asserts that the invading Aryans destroyed the Indus settlement. This view has also been corroborated by the Rig-Veda

Answer 2

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In 1821, while Metternich was still at Laibach with Tsar Alexander, the revolt of Prince Alexander Ypsilantis threatened to bring the Ottoman Empire to the brink of collapse. Wanting a strong Ottoman Empire to counterbalance Russia, Metternich opposed all forms of Greek nationalism.