Life history theory predicts that individuals adapt their life trajectories to the local ecology. One important ecological factor that influences the timing of certain life events is extrinsic mortality. Extrinsic mortality is a result of environmental hazards such as infectious diseases, predation, war, famine or accidents which is an age-specific risk that is not under the individual’s control. Previous studies in preindustrial and contemporary societies have shown that exposure to high extrinsic mortality during early childhood (0-7 years) can fasten individuals’ life history strategies characterized by earlier age of menarche, first pregnancy and birth. The present study investigates the impact of high extrinsic mortality during early childhood on the age at first marriage, age at first birth, out of wedlock fertility, and the length of birth intervals. Extrinsic mortality is measured in two ways: (1) mortality on district level, and (2) mortality on family level. On the district level we utilize crude death rates, and on the family level we study the effect of mother’s death, father’s death and siblings’ death. We predict that individuals who were exposed to high extrinsic mortality during early childhood will marry younger, start reproduction earlier, have shorter birth intervals, and will have a higher risk of giving birth out of wedlock.We use the Stockholm Historical Database (SHD), which contains records of the total population of the city of Stockholm for the period 1878-1926, to investigate our hypotheses. To analyze the impact of high extrinsic mortality during early childhood on the marriage and reproductive behavior, we select individuals who were born in the city of Stockholm between 1878-1905, who had at least one sibling (birth date and possible death date had to be known), and whose father’s socioeconomic status is known. Separate event history models will be estimated for men and women.