Yasuke: 10 Mind-Blowing Historical Facts From The Netflix Anime

Natsumaru, a warrior from the Iga Province, doesn't have a specific historical counterpart in history, but represents female warriors well-known at the time called Onna-musha - female warriors who fought in battle alongside their male counterparts. In the series, Natsumaru acts as Nobunaga's onna-musha and is one of his "seven samurai" (which was not part of history, but a nod to the famous Kurosawa film), having proven herself as a skilled fighter.

Natsumaru also refers to herself as a besshikime, a female bodyguard to important women under feudal lords. The distinction between besshikime and onna-musha appears to come from their weapons; where onna-musha commonly carried a long bladed polearm called naginata, besshikime were known for carrying swords in the way samurai did. Besshikime were also well-paid and highly respected protectors and members of individual warring courts.

Because Natsumaru was of the Iga Province, it's implied she may have also been a Kunoichi, or female ninja, which aligns with her work deceiving Nobunaga and his court, and passing information on to his enemies from her clan.