The era after Genghis Khan's death in 1227, when the largest contiguous land empire in history passed to his sons and grandsons and split into four vast khanates — the Yuan in China, the Ilkhanate in Persia, the Golden Horde on the Russian steppe, and the Chagatai realm in Central Asia. For roughly a century these states ruled or dominated lands from Korea and China to Persia, Central Asia, and the Russian steppe, knit Eurasia into one connected world under the Pax Mongolica, then dissolved into the nations that still remember them with both dread and pride.
The largest land empire in history did not die with its founder. When Genghis Khan died in 1227, the empire passed to his heirs and, within a generation, fractured into four separate realms — each ruled by his descendants, together stretching from China toward the edge of Europe, each soon adopting the faith and culture of the people it had conquered. The line that sacked Baghdad ruled Persia as Muslim sovereigns a few decades later. The roads they kept safe carried silk one century and the Black Death the next. To hold this era is to watch a single family inherit the world, divide it, and lose it.