Some sadhu orders, most famously the Naga sadhus, who go without clothing and cover themselves in ash, developed a martial tradition in the medieval and early modern period, organising into armed akharas that at times fought each other over pilgrimage rights and trade routes and served as mercenaries or armed retainers for regional rulers, a history documented in temple records and colonial-era accounts and still visible today only in ceremonial form, such as the akharas' processions with symbolic weapons.
That akhara structure still governs the most visible modern expression of sadhu life, the great Kumbh Mela gatherings, where the different akharas process to bathe in a fixed order of precedence, the shahi snan or royal bath, that has itself been the subject of dispute and occasional violent confrontation between orders in past centuries, now managed by heavy state coordination of crowds, sanitation and security at gatherings that draw enormous numbers of pilgrims and sadhus over the course of the festival, among the largest peaceful gatherings of human beings anywhere in the world.
Thirteen akharas are formally recognised today under the Akhil Bharatiya Akhara Parishad, the umbrella body that negotiates bathing order and represents the akharas in dealings with state Kumbh authorities, and each akhara maintains its own internal hierarchy of mahants and its own specific deity or founder-saint, so that the seemingly unified world of the sadhu orders is, on closer view, a federation of distinct institutions with their own property, discipline and succession rather than a single organised sadhu church.