People’s life courses are shaped by the complex interactions of contextual factors, of individual behavior, and of opportunities and constraints operating at the macro level. Demography studies these processes with a focus on particular transitions in the life course: birth, leaving home, marriage, and other transitions in civil status (divorce, remarriage, and transitions into widowhood), the birth and survival of offspring, migration, and finally the end of the life cycle—death.
Initial work on the ancient world focussed primarily on macro-level data, trying to establish overall trends in population development on the basis of census figures and other population estimates. This approach has received further impetus with the advent of survey demography (see Population Trends). More recently, attention has turned to single events in the life course. Core demographic studies have attempted to establish patterns and rates of marriage, fertility, migration, and mortality. Others have taken a complementary approach with a stronger focus on qualitative data. These support investigation of sociological, cultural, and economic aspects of demographic phenomena. The remainder of this article focusses on a concise evaluation of current understanding of marriage, fertility, migration, mortality, and population trends in the ancient Greco-Roman world.