The central labor institution of early Spanish America: a royal grant entrusting the labor and tribute of a group of indigenous people to a Spanish colonist, the encomendero, in exchange for a duty to protect them and instruct them in Christianity. In law the grant was of people's labor, not of land, and the indigenous were free vassals of the crown rather than property. In practice the system became a brutally coercive forced-labor regime that helped devastate the peoples it claimed to shelter, built the wealth of colonial Spain, and provoked one of history's first great debates over the rights of the conquered.
It was the polite word for plunder. After the conquest, Spain rewarded its conquerors not with slaves, in name, but with the labor and tribute of whole indigenous communities, handed over under a duty to protect and convert them that was mostly ignored. The crown called this entrusting; the law insisted the people were free subjects, not property, and that no land changed hands. On the ground it was forced labor in mines and fields, deadly enough that, with European disease, it helped collapse the very populations it claimed to shelter. The horror provoked the friar Bartolomé de las Casas to denounce it, drove the New Laws of 1542 that tried to curb it, and nearly sparked a colonist revolt when the crown reached for reform. This is the encomienda, the device that built the wealth of Spanish America on coerced hands and left Latin America its oldest pattern of inequality.