History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c39.s2.12

v1.c39.s2.12

The defeated tribes left India through Afghanistan and Iran, and were later known as the Zoroastrians; this is proven by a sudden extinction of the Harappan sites in Baluchistan and Afghanistan around second millennium B.C. Within a few centuries, the Sarasvatī valley people moved eastward on account of drought and shift in the river bed due to tectonic movement. They were in search of perennial water or sadānīra.