In several respects, the history of Indian peoples under Spanish colonial rule is strikingly similar throughout the New World. Wherever Europeans went they brought disease, and in their wake followed demographic disaster. Along with disease, the Spanish also introduced institutions and practices designed to subjugate native populations and to lay the foundation for a new colonial order. Thus, Indians from central Mexico to the southern highlands of Peru and beyond shared the experience of being brutally exploited under encomienda and repartimiento. Later, they would witness the emergence of latifundia, and many generations would toil on haciendas while others would continue to labor in mines or obrajes. Whatever the task, wherever it was performed, the lives of Spain's Indian subjects were always difficult and too often full of suffering and deprivation.

This book has examined the relation between indigenous populations in the north-central highlands of Ecuador and disease, especially infections introduced by Europeans during the sixteenth century. During the pre-conquest period, the unique characteristics that would later substantially influence the colonial experiences of the region's indigenous inhabitants first became apparent. They had had their own distinct economic and political institutions and had only recently been absorbed into the Inca state. That these societies were only partly assimilated into the Inca imperial system in 1534 meant that their experiences under Spanish rule would differ from those of their more fully integrated southern neighbors.

The introduction of Old World infections had transformed the complex, but relatively benign, disease environment of the northern Andes to one of extreme virulence by the middle of the sixteenth century.