INTERACTING FACTORS AFFECTING ILLEGITIMACY IN PREINDUSTRIAL NORTHERN ENGLAND

Illegitimacy in a historic, single community at Penrith, Cumbria (1557 -1812), has been studied using aggregative analysis, family reconstitu tion and time series analysis. This population was living under extrem e conditions of hardship. Long, medium and short wavelength cycles in the rate of illegitimacy have been identified by time series analysis; each represents a different response to social and economic pressures . In a complex interaction of events, the peaks of the cycles in wheat prices were associated with rises in adult mortality which promoted a n influx of migrants and a concomitant rise in illegitimacy. The assoc iation between immigration and illegitimacy was particularly noticeabl e after the mortality crises of the late sixteenth and early seventeen th centuries. Children of immigrant families also tended to produce il legitimate offspring. Native and immigrant families responded differen tly to extrinsic fluctuations, and variations in their reproductive be haviour were probably related to access to resources.