as in Mesopotamia and Egypt, early civilization in india emerged in river valleys. the indus river valleys supported a thriving civilization between 3000 b.c. and 1500 b.c. that was based on two major cities, harappa and mohenjo-daro. An advanced civilization- known as harappan o rindus civilization- prospered in these cities for hundreds of years and made significant political and social achivements. internal decline, however, weakened this civilization in the indus river valley. the final blow to the cities might have been an influx of new peoples. hope this helps you.