Ancient India - Dought caused the population of the Indus Valley to scatter from large urban centres to villages
Time: 21st Century BC
Place: Indus Valley (Present-Day Northwest India and Eastern Pakistan)
Details: In the early second millennium BCE, persistent drought caused the population of the Indus Valley to scatter from large urban centers to villages. Around the same time, Indo-Aryan tribes moved into Punjab from Central Asia in several waves of migration.