Oyamazumi-no-mikoto is a mountain deity (kami) in Shinto tradition, revered as the god of mountains and, by extension, associated with the sea and warfare in certain regional traditions. This deity is enshrined at Oyamazumi Shrine on Omishima Island in Ehime Prefecture, a site historically significant to warriors and seafarers who sought favor before undertaking perilous journeys or battles. Popular tradition links Oyamazumi-no-mikoto to blessings of fortune and protection, though such associations vary by locality and era rather than resting on a single fixed doctrine.