This chapter examines the history of ‘warrior asceticism’ in South Asia with a focus on the ‘gosain’ army of Rajendragiri and his disciples in eighteenth-century north India. It begins with a discussion of asceticism and power (including martial power) in Indic thought over the longer term, drawing on key concepts in the Ramayana and Mahabharata. Developments under the Mughals and post-Mughal successor states are also examined. Warrior asceticism experiences dramatic expansion, however, during the eighteenth century, a fact that is due principally (the author suggests) to the complementarity of yogic asceticism and the rise of infantry warfare in South Asia, often understood as part of a global ‘military revolution’. Though ‘Hindu’ warrior asceticism became an ideological font for much anti-British (and anti-Muslim) nationalist thought from the late nineteenth century, the gosain army of Rajendragiri’s disciples Anupgiri and Umraogiri was noteworthy for its role in buttressing British power in the geostrategic buffer region of Bundelkhand, as Company forces confronted the amassing armies of the Marathas during the second Anglo-Maratha War (1803–5).  Also contrasted are eighteenth-, nineteenth- and twentieth-century theorisations of yoga and violence, focusing on the reflections of Padmākar, Mān Kavi, Bankim and Gandhi.