This case study deals with mantra repetition and its role in the formation of religious and social identities. Correcting the widespread assumption that continuous mantra repetition is a timeless and universal practice, the study will argue that mantra repetition has a historical origin and must be studied against its cultural background. Preliminary research suggests that mantra repetition came to be used as a ritual tool or practice in its own right in the final centuries BCE. By the time of the emergence of complex Tantric systems in the middle of the first millennium CE, the practice had already firmly established itself across the religious traditions of South Asia. The aim of the planned case study is to reconstruct the history of mantra repetition and its diverse modes and forms. It will deal with the historical roots of mantra repetition, its diversification in late antiquity and the Middle Ages, and with the theory that it diffused from South Asia across Eurasia. A special emphasis will be placed on the important role that mantra repetition practices as well as counting aids used to keep track of repetitions (“prayer beads” etc.) played in the formation of religious and social identity. In particular, the interplay between Brahminical/non-Brahminical and Tantric/non-Tantric forms and modes of mantra repetition will be examined.