After over a month of illness, the leader of the Mongol Empire, Mongke Khan, had recovered enough to leave his tents and review his troops. Most Khans moved northward during the summer heat, but Mongke had decided to stay and see out the siege of Hechuan in southern China. He had been wounded by shrapnel in August, which had hardly fazed the Khan. However, while injured, his nurses had given him tainted water that produced a “blood plague” of diarrhea (what modern scholars believed was cholera).
Mongke spent much of his illness pondering the future of his empire that had already seen its share of internal warring. He had kept up good feelings with Batu in the west, but it was not difficult to imagine the Mongol forces being split. Electors needed to be better defined, leading Mongke to create an addition to Genghis's Yassa defining whose influence was significant and rules in case of a split vote. Later in his career, Mongke would use this law as a basis for a stronger support system among the princes to create something of a parliament for internal rule while the Khan worked to further the ancestors' goal of world conquest.
Mongke died in 1287, seeing his empire grow by the decade. His brother Hulagu Khan had defeated a combined force of the Mamluks and Franks at Ain Jalut and conquered Egypt, opening the gateway to Africa. Kublai had moved into Southeast Asia and dominated the islands of Japan on his third invasion attempt. Further Mongols had marched into Central Europe, where they had turned back in 1248 at the death of Güyük Khan. The battles there had been bloody as the Mongols struggled to adapt to the wetter weather and denser populations, but the Horde had always excelled at adaptation. They soon traded their bows for Arabic midfa (small cannons), eventually creating the precursor to the musket. By Mongke's death, the Mongols were approaching the Pyrenees Mountains.
His brother Kublai was elected after Mongke's death for a short reign that ended in 1298 with the Khan's death after a long illness. He had vouched for his son Temur to become Khan, but the elective princes distrusted his gluttony and drunkenness and chose a distant relation, Gentu. Conquests continued, wrapping up the whole of the Eastern Hemisphere in a Mongol Empire that stretched from the Forest Kingdoms of Ghana to the Scottish Highlands to the ice-block villages of the Arctic to the islands of Oceania. Strict organization kept the empire in line with severe penalties such as death for allowing a traveler to starve. In exchange for obedience, the people were marginally free to worship and seek employment as they chose.
Upon the discovery of the Western Hemisphere in the seventeenth century by explorers crossing the Bering Sea, Mongols launched a new wave of conquests (aided by the spread of smallpox) that filled their coffers with gold. Much of the wealth went into art, which in turn furthered scientific development that revolutionized the empire with networks of first telegraph lines, then radio waves, then satellite links. While much the same, society came under its own revolutions in the Empire with election of princes and an end to slavery.
The Mongol's next invasion would be of nearby planets, setting foot on the Moon on the 800th anniversary of Genghis Khan's birth. Using it as a light gravity-field launching ground for missions to Mars and Jupiter, research and mining facilities spread out through the Solar System. With the Terrestrial Planet Finder probe, the Empire's next step of conquest is soon to be found among the stars.
In reality, Mongke Khan died of his illness on August 11, 1259. As with all deaths of a Khan, the Mongol princes returned to elect the next, causing Hulagu Khan to leave the Middle East with the majority of his army. On September 3, 1260, the Mongol army under the Turkish general Kitbuqa would suffer defeat in an ambush by the Mamluk Egyptians at Ain Jalut in Palestine. While the defeat was on the outskirts of the empire and not influential to the Mongols, it gave the West great hope in proving that the Horde could be defeated. After Kublai Khan's reign (won from his brother Ariq Boke in civil war), the empire would begin to splinter into its many conquered lands, which were forever changed by their Mongol overlords.