then. One of his grandsons, Batu Khan, led Mongol armies into Europe in
 1237 and conquered Bulgaria, Moscow, Kiev, Hungary and Poland,
 forcing local rulers to pay tribute to the Golden Horde. Another grandson,
 Kublai Khan, conquered northern China and became the Yuan emperor in
 1271. His armies finally defeated the southern Sung in 1279 and his
 dynasty ruled until 1368. Across Eurasia, a Mongol postal system and a
 roadway network extended from China to Turkistan, Persia, and Russia,
 fostering overland trade that brought gunpowder, the compass and printing
 to Europe from China. Along these routes, Marco Polo travelled from
 Venice to China and back. But the Mongols could not conquer India.
 Having failed repeatedly to conquer India, Mongols withdrew from the
 Indus basin to concentrate their powers elsewhere, with spectacular
 success.
  The Mongols extended their hegemony over a major part of the Eurasian
landmass, from the Daruble to the Pacific for the better part of two centuries.
  https://sites.google.com/site/mrvailsclass2/mongolian-empire-and-feudal-