Expanding from a number disparate Mongolian tribes brought together by the future-Genghis Khan, the Mongol Empire went on to become the single largest contiguous empire in recorded history. Beginning in the steppes, it eventually stretched from the Sea of Japan to the gates of Vienna, Austria, and from the Republic of Novgorod in the north, to the Indian subcontinent in the South.
War with the Assassins
During the latter part of the 13th century, the Mongols became the major enemy of the Assassins. In 1227, the Mentor of the Levantine Assassins, Altaïr Ibn-La'Ahad, his son Darim, and the Mongolian Assassin Qulan Gal were responsible for the death of Genghis Khan, whom they suspected of wielding a Piece of Eden in explanation of his rise to power.
Thirty years later, in 1257, the Mongols finally reached and besieged the Assassins' fortress of Masyaf, partially destroying and seizing it and forcing the Assassins to scatter throughout Europe, Africa and Asia.
After the siege, a Mongol patrol intercepted the fleeing Assassins and famed explorers - Niccolò and Maffeo Polo - and obtained the Codex of Altaïr from them. Years later, Niccolò's son, Marco, traveled to the court of Kublai Khan, grandson of Genghis Khan, and retrieved the Codex from him.
In the 1530s, Zhang Yong, one of the Eight Tigers, plotted to allow passage of the Mongols, led by Altan Khan, into China by opening the gates of the Great Wall. To prevent this from happening, the Assassin Shao Jun infiltrated the three gate houses and closed the gates. A massive battle between the Mongol army and the Ming Dynasty troops subsequently ensued outside the wall, with the latter eventually emerging victorious.