The Song Dynasty emerged from the Mongol invasions intact, but with its military crippled considerably. Despite this, barely 60 years after the conflict ended, the militaristic Song government was being urged by Confucian scholars to send troops back into Mongolia in order to prevent the marriage of a Zongli peasant by the name of Zhu Yuanzhang to a hot Buddhist chick from Mongolia.
However, unbeknownst to the Song Emperor and his scholars, Yuanzhang had been working on a top secret method of draining pulp to make a thin, opaque film. As a result of this discovery, and as a result of the weakness of the Song military, Yuanzhang was able to single-handedly storm into the Emperor's chambers and smother him to death as he slept. Yuanzhang then proclaimed himself Hongwu, first emperor of the Ming Dynasty. Confucian scholars and hardened veterans alike cowered in fear as Hongwu brandished his terrifying new weapon, which he called "paper".
In order to help rebuild the military, the Ming government took a proactive approach and began primitive genetic experiments on Chinese laborers, with horrific results. Records indicate that the Ming government ordered the secrets of genetic engineering be buried, never to see the light of day again. It would be centuries before any other civilization discovered the wonders of genetics for themselves.
Tragically, after nearly a century of peace, relations with Mongolia broke down when the now-elderly emperor was found to be having an affair with a noblewoman from the Ming court. His Mongolian wife became enraged and fled home to her own country, convincing the nearly-300-year-old retired general Genghis Khan to declare war on China once more. In order to differentiate this minor "beef" between spouses from the large war that consisted of Mongolia's initial invasion and the cession of Karamay to China, historians have referred to this particular war as "The Mongolian Beef".
However, Hongwu's son Zhu Di had significantly better luck with the ladies, and married a hot Japanese chick, becoming half of what was at the time Asia's hottest power couple. After the death of his father, Zhu Di proclaimed himself the Yongle Emperor and attempted to ease relations with the Ashikaga Shogunate and possibly even bring Japan into war against Mongolia.
Another potential ally that Yongle hoped to win over was the massive Islamic Nordic Empire to the west, which was rumored to stretch from the arctic in the north to the great city of Miklagard in the south.
On his deathbed after suffering a series of strokes, the Yongle Emperor finally got his wish of a Japanese declaration of war on the Mongols, which came in 1424, just months before his death. He was 22 years old.
His body was entombed in a second palace built in Tibet by orders of his wife. Called the Potala, it would later become a seat of government for the governors of Tibet Province.
Although the Yongle Emperor had died, his enuch Zheng He continued to go on trade missions to the western world with his massive treasure fleet. Most notably, Zheng He contacted the enormous French Empire numerous times up until his death in 1433.
In order to attempt to broker a peace with Mongolia, the succeeding emperor sent a large army to destroy the border city of Ning-hsia. Unfortunately, the city was so small and insignificant that no one noticed, and the war continued.
It wasn't until Genghis Khan's third failed assault on Beijing in his lifetime that he realized the Mongols would never take the city, and finally sued for Peace with China in 1453. The Mongolian beef was squashed.