The yamabushi (literally, "sleeps in the mountains"), are Japanese mountain ascetics. The term "yamabushi" is often associated with the Japanese mountain worship known as "Shugendo," but it is a catch-all term that can be applied to anyone who seeks enlightenment by living alone in the mountains.
Yamabushi have existed in Japan since before recorded history. Some of the ascetic practices typically associated with the yamabushi include standing under waterfalls, hanging from precipices, fasting for inordinate amounts of time, or running long distances. In earlier times, the yamabushi were credited with shaman-like powers such as healing by laying-on of hands, divining, and knowledge of the future, and would be sought out in times of desperate need.
The yamabushi were approached with caution, however. Although they were objects of veneration and respect for their arduous lifestyle and their special powers, they were also somewhat feared for their mysterious, inscrutable ways and the fact that you never knew what nasty tricks they might have learned from tengu or foxes.
Yamabushi generally led solitary, peaceful existences, but occasionally there were leagues of warrior yamabushi who united for common defense or banditry.
Today the yamabushi are disappearing as urban sprawl encroaches on Japan's last untouched mountains and the lure of modern amenities makes living in the mountains less appealing. Modern yamabushi are much more likely to have a home nearby or even a family and spend only part of their time alone in the mountains. Nevertheless, as long the mountains remain a powerful symbol in the Japanese psyche, there will doubtless always be yamabushi of some sort.