Mongols and Yuan Dynasty
The Mongol Empire (1206-1368) had a leader named Genghis Khan, meaning "Universal Ruler". The Mongol Empire had an elective monarchy and the capitals were Dadu, Avarga, and Karakorum. The main achievements were the Yassa code which was an order where Genghis Khan allowed religious freedom and the "Secret History of the Mongols."
The Yuan Dynasty (1271-1368) had a leader named Kublai Khan, but was founded by Genghis Khan. The Yuan Dynasty had an elective monarchy and the capital was in Khanbaliq. The main achievements were advanced polynomial algebra, physicians and developed landscape painting.
http://afe.easia.columbia.edu/mongols/china/china.... -Mongol Empire
http://www.travelchinaguide.com/intro/history/yuan/ -Yuan Dynasty