Mongol conquests (1258): Baghdad

Deaths are among the least certain in this atlas: published scholarly ranges often sit around 20-40 million across the thirteenth century, with some older figures higher and many local studies lower. Siege massacres (Baghdad 1258, Zhongdu, Nishapur in the chronicles) sit beside famine and displacement. Treat every total as a band, not a census.

The same empire that destroyed cities also ran relay posts (yam), protected some trade, and moved artisans and astronomers across Eurasia -- the "Pax Mongolica" of later textbooks. English memory arrives through Travels of Marco Polo, school maps of a pink-brown blob, and a thin film canon. Korean memory is more specific: the 1231-59 Goryeo wars and the forced 1274/1281 expeditions toward Japan.

Steppe unification, city sieges, and a Eurasian afterlife The Mongol wars were a technology of mobility and terror that became, in the successor khanates, a system of tax, post and pluralism -- at a demographic price still counted in ranges. Chinggis's early wars were against steppe rivals, then Western Xia and Jin. The 1215 fall of Zhongdu (Beijing) is an early named urban catastrophe in the Chinese record.