Because the Indus Valley had flourished for 1000 years and then disappeared out of nowhere and didn't leave much behind and we don't know what happened to them to make them disappear
In today's Pakistan.
During the Harappans (Indus River civilization) they spoke a language that is now unknown for today. Archaeologist couldn't decipher its language because of the lack of evidence provided there which may be because of the flooding that occurred.
The Indus Valley Civilization was a Bronze Age civilization (mature period 2600-1900 BCE) which was centred mostly in the western part of the Indian Subcontinent and which flourished around the Indus river basin. Primarily centered along the Indus and the Punjab region, the civilization extended into the Ghaggar-Hakra River valley and the Ganges-Yamuna Doab, encompassing most of what is now Pakistan, as well as extending into the westernmost states of modern-day India, southeastern Afghanistan and the easternmost part of Balochistan, Iran.
Paddy farming is an enduring trait of the Indus Valley civilizations. it is present in many modern Asian cultures even to this day.
In the Indus River valley in today's Pakistan.
Indus River Valley.
Two of the most prosperous civilizations flourished here. They are the Indus Valley Civilization and the Hwang Ho Civilization. These were one of the most populous civilizations too, thats the reason why the population in this region even today is very dense.
Q: Which geographic factor is most associated with the decline of the Indus Valley civilizations?A: Isolation from other civilizations
The Indus Valley Civilization was a highly urbanized civilization. As a result there was a large section of the population that was not directly involved in agriculture but instead relied on the farmers in the rural areas for their food, a pattern which is consistent with cities today. In the absence of any scriptural evidence it can only be presumed that the Indus Valley Civilization had trade relations with places as far as Mesopotamia. - Excavated materials in Mesopotamia suggest that they might have had trade relations with Indus Valley Civilization by a sea route since some of the seals have pictures of boats. It can also be suggested that there was trade taking place because the resources required by the civilization were located over a large area. The Indus Valley Civilization people might have used weights and other measures so some of the artifacts discovered seem to be objects used for weighing. An interesting feature is that the weights appear to be based on a multiple of sixteen systems, a system which continued in India until the metric system was adopted. -
In today's Pakistan.
It is in Pakistan.
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