Indus Valley Civilization Probably causes of Decline
Some people say that there was a sudden end to it due to an unexplained catastrophe.
The river Indus Valley Civilization is well-known for its mighty floods which overwhelm and wash away cities and villages.
A changing climate might lead to a progressive deterioration of the land and the encroachment of the desert over cultivated areas.
The ruins of Mohenjodaro built on the layer upon layer of sand raising the ground level of the city. This compelled the inhabitants to build higher on the old foundations.
Some excavated houses have the appearance of two or three-story structures. Yet they represent a periodic raising of the walls to keep pace with the rising level.
The province of Sind was rich and fertile in ancient times, but from medieval times onward it has been largely desert.
It is probable that these climatic changes had a marked effect on the people of those areas and their ways of living.
In any event climatic changes must have only affected a relatively small part of the area of this widespread urban civilization. However Indus valley spread right up to the Gangetic Valley, and possibly even beyond.
We have really not sufficient data to judge. Sand, which overwhelmed and covered the ancient cities, also preserved them.
Aryan and Invasion of Other Races
While there is a definite sense of continuity between the Indus Valley civilization and later periods.
There is also a kind of break not only in point of time but also in the kind of civilization that came next.
This latter civilization was probably more agricultural than Indus Valley Civilization. Though towns existed and there was some kind of city life also.
The emphasis on the agricultural aspect may have been given to it by the newcomers. The Aryans who poured into India in successive waves from the north-west.
The Aryan migrations might have taken place about a thousand years after the Indus Valley period.
The tribes and peoples came to India from the north-west from time to time, and became absorbed in India.
The first great cultural synthesis and fusion took place between the incoming Aryans and the Dravidian.
Out of this synthesis and fusion grew the Indian races and the basic Indian culture, which had distinctive elements of both.
In the ages that followed there came many other races. This includes Iranians, Greeks, Parthians, Huns, Turks; they came and got absorbed.
It is odd to think of India, with her caste system have a astonishing capacity to absorb foreign races and cultures.
Perhaps it was due to this that she retained her vitality and rejuvenated herself from time to time.
The Muslims, when they came, were also powerfully affected by her. The foreigners (Muslim Turks), like the Sakas, yielded to the assimilative power of Hinduism.