Five dynasties, or families, ruled ancient China for more than 6,000 years. The last one of the ancient period, the Han dynasty, ruled around the same time as the ancient Roman Empire.

Analysis of ancient DNA and grave goods from burials suggest that princesses helped to build a "massive empire" stretching from Kazakhstan to Mongolia.

Ancient DNA, combined with the fruits of recent archaeological digs, is spilling the secrets of one of the ancient world’s most powerful political forces.