Christopher Columbus
Since the late 20th century, historians have criticized Columbus for initiating colonization and for abuse of natives. Among reasons for this criticism is the poor treatment of the native Taíno people of Hispaniola, whose population declined rapidly after contact with the Spanish. Columbus required the natives to pay tribute in gold and cotton. Modern estimates for the pre-Columbian population of Hispaniola are around 250,000–300,000. According to the historian Gonzalo Fernandez de Oviedo y Valdes, by 1548, 56 years after Columbus landed, and 42 years after he died, fewer than 500 Taíno were living on the island. The indigenous population declined rapidly, due primarily to the first pandemic of European endemic diseases, which struck Hispaniola after 1519. The natives had no acquired immunity to these new diseases and suffered high fatalities. There is also documentation that they were overworked.
Slavery in the Spanish New World colonies
When Spain first enslaved Native Americans on Hispaniola, and then replaced them with captive Africans, it established unfree labor as the basis for colonial mass-production. It was believed by Europeans that Africans had developed immunities to European diseases, and would not be as susceptible to fall ill as the Native Americans because they had not been exposed to the pathogens yet. In 1501, Spanish colonists began importing enslaved Africans from the Iberian Peninsula to their Santo Domingo colony on the island of Hispaniola. These first Africans, who had been enslaved in Europe before crossing the Atlantic, may have spoken Spanish and perhaps were even Christians. About 17 of them started in the copper mines, and about a hundred were sent to extract gold. As introduced diseases decimated Caribbean indigenous populations in the first decades of the 1500s, enslaved Blacks from Africa ("bozales") gradually replaced their labor, but they also mingled and joined in flights from slavery, creating mixed maroon communities in all the islands where Europeans had established chattel slavery. The newly enslaved workers continued to arrive in Spanish colonies as colonials imported them directly from Portuguese traders, who in turn purchased them from African traders on the Atlantic coast. With the increased dependency on enslaved Blacks developed also distinctive racial hierarchy and the hardening of racial ideologies, buttressed by prior ideologies of differentiation as that of the Limpieza de Sangre (en: Blood Purity). In the vocabulary of the time, each enslaved African who arrived at the Americas was called "Pieza de Indias" (en: a piece of India). Asiento (en: chair) was the name for the agreement between the Spanish authorities and slave traders. During the 16th century, the Spanish colonies were the most important customers of the Atlantic slave trade, claiming several thousands in sales, but the Dutch, French and British soon dwarfed these numbers when their demand for enslaved workers began to drive the slave market to unprecedented levels.