Fakirs
The Fakir tradition as it relates to performing is a very old one, and typically includes acts that bring peril to the physical body.
Examples are bed of nails, human pincushion, fire-eating, and sword swallowing. The word fakir comes from the Arabic word faqīr, which literally means "poor man," and encompass the spiritual disregard for pain and body harm. For our usage Fakir acts are those performed in sideshow, and linked mainly to the Fakir traditions of India, and more specifically of Hindu religious ascetics that go by names such as gosvāmin, sadhu, and bhikku.
The exoticism and danger of these acts have kept them popular for thousands of years in the East,, and for hundreds of years within the Western tradition of showmanship and extreme performance.