For the fact is that these cities were certainly not growing because of a tremendous upsurge in the fertility of urban women. (Cities have never grown to any appreciable degree through an excess of births over deaths. Their birth rates are always too low, and in preindustrial and early industrial cities their death rates were always too high. See Peterson, 1961:Part II; Freedman [ed.], 1964.) No, these cities were growing because they were receiving massive influxes of rural populations.

XREF: Connects to modern urbanization debates about rural-to-urban migration and megacity growth.

DEFINE: Clarifies the mechanism of urban growth in preindustrial cities — distinguishing rural in-migration from natural population increase as the true driver.

Lyn H. Lofland, World of Strangers_ Order a…, loc. 317