The people of the first nomadic empire left no written records, but from 200 bc they dominated the heart of Asia for four centuries, and changed the world in the process. The Mongols, today's descendants of Genghis Khan, see these people as ancestors. Their rise cemented Chinese identity and inspired the first Great Wall. Their descendants helped destroy the Roman Empire under the leadership of Attila the Hun. We don't know what language they spoke, but they became known as Xiongnu, or Hunnu, a term passed down the centuries and surviving today as "Hun," and Man uncovers new evidence that will transform our understanding of the profound mark they left on half the globe, from Europe to Central Asia and deep into China.