Long before there was the British Empire, or Napoleon established his – long before any Europeans had come out of the Dark Ages even – a group of ethnic tribes called Mongolians came to power in what is now northern China. One of its early leaders, Tiemuzhen, unified the disparate tribes, taking the title Genghis Khan – ruler of the world. The unified Mongolian Empire swept over nearby dynasties and then went into northern Asia and into Russia and Europe.

On this day, December 18, in 1271 Kublai Khan, grandson of Tiemuzhen, established the Yuan Dynasty, which lasted for nearly a century. He proclaimed himself emperor, later called Yuan Shizu.

Kublai Khan’s territories included modern-day China, united under a single ruler for the first time. To maintain a fair rule, he established a meritocratic system of government, appointing those proving themselves the most able to positions of power. Kublai Khan centralized power, modernized the economy – creating some of the first paper currency – built roads, and for a while cultivated culture that would influence even the great explorer Marco Polo. At its height, Kublai Khan’s empire ruled from Tibet to Siberia, a territory spanning four million miles.