CONQUEST and colonization of the Americas by Europeans were accompanied by an unprecedented blending of Old World and New World diseases, ethnomedical systems, and plant-based pharmacopoeias. Romantic visions of a salubrious American Eden, free of illness and aging, yielded to the reality of epidemic and premature death. Indigenous peoples succumbed in droves to exotic viruses; Mediterranean colonists battled new tropical maladies; and African captives, overworked and underfed, fell prey to both. Colonial physicians, few in number and often self-trained, doled out the medical care then known to late medieval and Renaissance Europe. Barbers, surgeons, bleeders, and priests, whose views of causation ranged from astrological imbalances to the effects of evil spirits and bad air, responded to the needs of the growing European population. But neglect by slave owners and the exorbitant cost of physician services and pharmaceuticals forced African chattel to tend to their own medical problems. African priests, herbalists, and magicians, initiated into their trade before passage to the Americas, pursued their vocation to the extent possible in their new urban or rural settings. Firmly established in colonial times, African-based medicine, magic, and their associated plant pharmacopoeias have persisted and in many cases flourished in the Americas. ARRIVAL AND SURVIVAL The demographics of the slave trade most clearly delimited where and to what degree African magico-medical systems diffused into the New World. Where the volume and duration of slavery were heavy and protracted, African-based ethnomedicine not only survived but also in some cases came to predominate. Brazil, which absorbed more than four million African immigrants, retains African religious and medical systems so orthodox that, until recently, Nigerian priests undertook pilgrimages to Brazil to rediscover ceremonies long forgotten in Africa. With a total of approximately five million slaves imported, the old Spanish Main exhibits magico-religious systems scarcely different from those in Africa. By contrast, North America, which received only half a million Africans during the entire slave trade (Rawley 1981, 428), witnessed minor survival of their ethnomedical systems. Cultural diffusion from Africa to the Americas was indirectly fostered by the insufferable conditions of plantation existence. Treatment of slaves varied among owners, ranging from benign paternalism to sadism. Where conditions were most brutal, high mortality combined with sub-replacement-level fertility to generate a constant demand for fresh captives. In the Dutch colony of Surinam, 300,000 Africans arrived between 1668 and 1823, but scarcely 50,000 descendants survived at the end of that period (Price 1976). In Rio de Janeiro, even after three centuries of sustained slave traffic, more than 73 percent of the 1832 slave population was African born (Karasch 1987). In Latin America, at least, the captive labor force was numerically dominated by slaves born not in the Americas but in Africa. Included among the ranks of these newly arrived laborers were priests, magicians, and herbalists, who frequently retained, even as slaves, a measure of their previous status. This, in turn, facilitated the survival of a social hierarchy, necessary to the existence of a shaman class, and reinforced the collective knowledge of African ethnomedicine among the resident black population. The religious division between Protestantism in British North America and Roman Catholicism in Latin America also contributed to the degree of cultural retention. Whereas the simpler ritual of Protestant sects conflicted with the complexities of African religion (Camara 1988, 304), Roman Catholic liturgy had some structural similarities with African religions: ancestor worship, elaborate ritual and offerings, and, most importantly, polytheism. For Roman Catholics polytheism meant devotion to the hagiology of saints; for Africans, faith in the power of a pantheon of deities. …