What do historians believe happened to the Indus Valley Civilization? Describe (in a sentence) one of the three theories historians have about their decline.
One of the three theories historians have about the decline of the Indus Valley Civilization is that it suffered a catastrophic ecological change, such as a significant shift in the course of the river, causing the civilization to collapse due to the loss of agriculture and trade.
Historians believe that the Indus Valley Civilization declined due to a combination of natural disasters, such as an arid climate change and the drying up of the Saraswati River.
Historians believe that the decline of the Indus Valley Civilization could be attributed to either environmental factors such as a major drought or earthquake, the arrival of the Indo-Aryans who replaced the existing culture, or internal social and political unrest leading to the collapse of the centralized state.
