This paper draws attention to the pervasiveness of life stage concepts in human cultures and advocates the creation of a new field of study on indigenous life stage concepts. First, historical and cultural examples are presented to illustrate the widespread use of life stage concepts across times and places. Then, sociological research on the institutionalization of life stages in the 19th and 20th centuries in industrial societies is summarized, but with a new interpretation of how those life stage concepts arose. Next, the idea of life stages as master narratives is proposed, as a way of explaining how life stages provide the raw material for individuals to construct a personal identity narrative. The paper concludes by proposing that the exploration of indigenous life stage concepts is an exciting new potential field of study.