The Mongols conquered China — the largest, richest, most populous country on earth — and then did something no nomad conquerors had done: they stayed, moved the capital to Beijing, and ran the whole thing. For a century, the world's largest economy answered to a khan.
The empire in images
The rise
Kublai Khan, grandson of Genghis, spent decades grinding down the Song — the conquest took 45 years, the longest and hardest campaign of the Mongol expansion, because Song China was rich enough to fight back with gunpowder, fortifications, and a navy. The steppe had never met resistance like it.
In 1271 Kublai proclaimed the Yuan dynasty — a Chinese dynastic name for a Mongol regime — and in 1279 the last Song resistance drowned at Yamen. China, conquered whole for the first time by outsiders, now belonged to the steppe. The khan became the Son of Heaven, and meant it.
The zenith
Kublai built Khanbaliq — “the Khan's city,” today's Beijing — as his capital, and ran China as the richest province of a Eurasian empire. The Grand Canal was extended north to feed the capital; paper money — the famous “flying cash” that so astonished Marco Polo, as he tells it — financed the state; and for the first time, China was plugged directly into a continent-spanning trade network, from the Pacific to the Black Sea.
The Yuan court was a strange, glittering hybrid: Mongol khans performing Chinese imperial ritual, Tibetan lamas as spiritual guides, Muslim financiers running the treasury, and Venetian merchants — Marco Polo among them, by his own account — serving as administrators. It shouldn't have worked. For a while, it did.
The fall
It didn't last, because the Mongols never solved the succession problem and never won the loyalty of the Chinese scholar class they excluded from power. Factional purges, paper-money inflation, and Yellow River floods that killed hundreds of thousands turned discontent into rebellion. An empire run as a family business eventually gets treated like one.
The Red Turban Rebellion — part peasant revolt, part millenarian movement — swept the south after 1351; its leader Zhu Yuanzhang, a former beggar-monk, took Beijing in 1368 and proclaimed the Ming. The last Yuan emperor fled to the steppe, where his descendants kept calling themselves khans for centuries. The steppe took China, and China — slowly, inevitably — took the khans.
The Yuan's most permanent legacy is a city: Beijing. Every dynasty since — Ming, Qing, and the People's Republic — has ruled China from the capital Kublai built. The Grand Canal's northern reach, the idea of China as a multi-ethnic empire, the Yuan map that is essentially modern China's: all Mongol bequests.
And there is Marco Polo's account — true, embroidered, or somewhere between — which put China in the European imagination for good and helped launch the age of exploration. The Mongols conquered China and became Chinese emperors: the steppe's greatest victory, and its most complete assimilation.