Question

Which writers say the harappan people were overthrown by the aryans ?

Answer 1

There are several theories related to the the end of Harappan civilization.

The Aryans, and Indo-European tribe, may have overepowered the Harappans and thus ended their reign. This theory was put forth by British Archeologist Mortimer Wheeler, Director-General of the Archeological Survey of India

Another theory was climactic changes that forced Harappans to leave their cities and migrate to other places in smaller groups.