Recent works in historical demography have demonstrated that migration and geographical mobility were fundamental components of life in colonial Hispanic American society. Studies using vital registers to trace migration between parishes have revealed a record of mobility that was truly ubiquitous. In New Spain, among the isolated settlements of the periphery and throughout the more established towns and villages of the settled core, people frequently changed residence. In the colonial jurisdictions of Central America, migration was common. Towns were often abandoned as resources and locational advantages played out and movement into and out of the region remained constant. Similar patterns of mobility persisted at all scales throughout the pueblos and provinces of South America. Entire native communities were displaced while within the Hispanic cities of the empire, populations fluctuated widely and persistence rates remained low. In no part of the colonies, however, was geographical mobility as pronounced as it was in the mining regions, the centers of exploitation, settlement, and expansion. On the northern periphery of New Spain, where free labor was the rule and where the silver centers competed with each other for workers, migration was especially widespread.

The purpose of this chapter is to uncover some basic patterns and relationships that characterized migration in this northern mining economy. After exploring the ecological basis and economic context for migration in the north, two key issues are examined: (1) the relationships between the patterns of development that mining centers followed and (2) the dimensions of the migration fields that formed around the centers; and the selective nature of migration as displayed in the socio-economic and demographic characteristics of migrants.