Proximate Factors of European Conquest

Key Insight

The infectious diseases prevalent in crowded Eurasian societies, to which many Eurasians had developed immunity or genetic resistance, were critical proximate factors in the conquest. These included the most lethal diseases in history, such as smallpox, measles, influenza, plague, tuberculosis, typhus, cholera, and malaria. In contrast, pre-Columbian Native American societies were only certainly afflicted by non-syphilitic treponemas. This continental disparity in harmful germs paradoxically resulted from Eurasia's abundance of useful livestock, as many human epidemic microbes evolved from diseases of the domestic animals with which food producers came into daily close contact around 10000 years ago. Additionally, villages and urban societies arose later in the Americas, and inter-regional trade was less extensive, limiting the spread of potential pathogens.

Technological differences were crucial. By 1492, complex Eurasian societies extensively used metals—initially copper, then bronze, and finally iron—for tools, whereas Native American societies primarily used stone, wood, and bone, with limited local copper tools for ornaments. Eurasian military technology was far superior, employing steel swords, lances, daggers, firearms, artillery, and solid steel or chain mail armor. Native Americans used less effective weapons like stone/wood clubs and axes (occasionally copper in the Andes), slings, bows and arrows, and quilted armor. Critically, Native American armies lacked animals to counter European horses, which provided a decisive advantage for assaults and rapid transport until some Native American societies adopted them.

Eurasian societies had significant advantages in power sources, moving beyond human muscle to utilize animals (cattle, horses, donkeys) for plowing, grinding grain, and water management. Waterwheels, tidal mills, and windmills proliferated from Roman times through the Middle Ages, powering diverse manufacturing processes from crushing sugar to sawing wood, marking an 'industrial revolution' long before steam power. By 1492, all these operations in Eurasia still relied solely on human muscle in the Americas. Furthermore, the wheel was fundamental to Eurasian land transport (animal-drawn vehicles, wheelbarrows, pottery, clocks) but existed only in Mexican ceramic toys in the Americas. Eurasian sea transport featured large, ocean-crossing sailing ships with advanced navigation tools like sextants and magnetic compasses, sternpost rudders, and cannons, vastly superior to the wind-dependent rafts used for trade in the New World, one of which Pizarro's ship easily captured.