Niijima Yae (新島八重), born Yamamoto Yae (山本八重), also known as Yamamoto Yaeko , was a Japanese onna-musha, educator, nurse, and scholar of the late Edo period who lived into the early Shōwa period. Her samurai family belonged to the Hoshina clan, loyal to the Tokugawa Shogunate. Skilled in gunnery, she helped defend the Aizu Domain during the Boshin War, earning her the nicknames “Nightingale of Japan” and “Bakumatsu Joan of Arc”.

Onna-musha (女武者) is a term referring to female warriors in pre-modern Japan. These women fought in battle alongside samurai men. They were members of the bushi (warrior) class in feudal Japan and were trained in the use of weapons to protect their household, family, and honour in times of war. They also have an important presence in Japanese literature, with Tomoe Gozen and Hangaku Gozen as famous and influential examples representing onna-musha.