Some 4,000 years ago, the mighty Harappan civilization accounted for 10% of the entire global population. Suddenly, this once-great society collapsed. What happened to the Harappan civilization? Why did the Harappan Civilization Collapse? The Harappan, or Indus, sprouted up 5,200 years ago. It grew into an ancient powerhouse, covering a massive area of 386,000 square miles,…