A graph superimposes the growth–decline curves of major Late Rider Empires, from 1200 to 1800. This was a period of shift from horses to sails. West European feudalism indirectly led to respect for law and a curiosity revolution. Inciting exploration, the latter began to give rise to transoceanic empires, first of all Spanish. But at first, Mongol horsemen seized a record-size area, unsurpassed among land-borne empires. Up to 1750 all truly large empires except Spanish remained land bound: Manchu Qing, Russia, Ottoman, and Mughal. The burgeoning French, Portuguese, and British empires were still modest. Much of the Mongol hold meant sparsely populated superficial tribute area, but by conquering China the Mongol empire also became the world’s most populous. Later on, Ming, Mughal, and Qing shared this eminence. Nomad empires were a phenomenon that rose and ended with the Rider phase. The Inca and Aztec empires retraced from scratch the human self-domestication process that the Old World underwent thirty-five centuries earlier, but they still lacked metals and the wheel.