Mongol conquest of the Song dynasty Mongol conquest of the Song dynasty The Mongol conquest of the Song dynasty under Kublai Khan (r. 1260–1294) was the final step for the Mongols to rule the whole of China under the Yuan dynasty. It is also considered the Mongol Empire's last great military achievement. Before the Mongol–Jin War escalated, an envoy from the Song dynasty arrived at the court of the Mongols, perhaps to negotiate a united offensive against the Jin dynasty, who the Song had previously fought during the Jin–Song Wars. Although Genghis Khan refused, on his death in 1227 he bequeathed a plan to attack the
Mongol Empire which carved through the Altai mountains. After his enthronement, Ögedei further expanded the road system, ordering the Chagatai Khanate and Golden Horde to link up roads in western parts of the Mongol Empire. Kublai Khan, founder of the Yuan dynasty, built special relays for high officials, as well as ordinary relays, that had hostels. During Kublai's reign, the Yuan communication system consisted of some 1,400 postal stations, which used 50,000 horses, 8,400 oxen, 6,700 mules, 4,000 carts, and 6,000 boats. In Manchuria and southern Siberia, the Mongols still used dogsled relays for the yam. In the Ilkhanate, Ghazan restored the