This dissertation explores changes in fertility and family formation in South Korea, a setting in which rapid demographic changes have taken place since the early twentieth century. Despite active debate and discussion among experts and policymakers, knowledge is still limited in regards to the country’s significant demographic changes. I take advantage of Korean census samples data from 1966 to 2010, which span birth cohorts from pre- and early-transitional stages to post-transitional stages, which comprise the entry stage of the second demographic transition. From a cohort perspective, I use diverse demographic methods to analyze three different aspects of fertility and family formation—fertility differentials, marriage delay, and fertility concentration.

The findings illustrate how fertility and marriage patterns have changed over generations and range from a politically tumultuous period, which includes World War II, liberation, and the Korean War, to an advanced economic period. By and large, the three studies suggest that until 1960, fertility and family formation converged as per social norms and leadership guidelines. Then, marriage and childbearing behaviors began to diversify and variation by social groups increased for cohorts born during and after the 1960s. The phrase “convergence towards diversity” captures the reversal of demographic trends within the country. Taken together, this dissertation advances our understanding of how fertility and family formation have changed in South Korea, which has been on an intense demographic journey from pre-transitional fertility through very low fertility, and currently headed toward another destination.