South Korea is experiencing the fastest aging of its population in world history, and its dementia population has grown swiftly in the past three decades. This chapter proposes the country’s significance as a case of interest for understanding global population aging and the associated increasing dementia population. A brief history of South Korea, transforming from an agricultural society to a major industrialized nation in less than half a century, demonstrates how major societal changes accompanying industrial development and modernization in a relatively short period have shaped the population aging of a country and its older adults’ risks for dementia. Studies of cognitive aging among elderly Koreans have found greater effects of education on cognitive performance compared to their counterparts in developed countries. As the role of formal education in cognitive development and its moderating effects on neurodegeneration have been found consistently, lack of education has significant consequences on the prevalence of dementia in elderly Koreans, especially women. This has important implications for global aging and dementia epidemiology, as the current increase in the global dementia population is most concentrated in developing countries.