For 10 points, name this Mongol ruler of China, the grandson of Genghis.
This emperor divided his people into four social classes based on race. He made paper money the sole currency in China. This man's chief architect, Liu Binzhong, constructed the city of Dadu for him. He came to power after defeating his brother, Ariq Boqe, in a civil war and conquering the remnants of the Southern Song Dynasty. This founder of the Yuan Dynasty attempted to invade Japan, but lost the Battle of Hakata Bay when a huge storm called the kamikaze destroyed much of his fleet. For 10 points, name this Mongol ruler of China, the grandson of Genghis.
This emperor divided his people into four social classes based on race.
Kublai Khan [or Khubilai Khan; or Kubla Khan]