The Mongol Empire

In 1206 the steppe tribes united under Genghis Khan. With fast horse archers, strict discipline and terror, the Mongols conquered north China and Central Asia, killing millions.

His sons and grandsons took Russia, Persia and all China, sacking Kiev and Baghdad. Only the Mamluks of Egypt, the sea around Japan and the deaths of khans stopped them.

The empire split into four khanates, but for a century the Mongol peace let goods, ideas and travellers like Marco Polo cross Asia. It also carried the plague.