Miyamoto Musashi was born into a samurai family in Miyamoto village in the Harima province. His full name was Shinmen Musashi no Kami Fujiwara no Genshin, and his childhood name was either Bennosuke or Takezo, it is unknown which. Musashi took his name from his birthplace, Miyamoto village.

Musashi's father was a samurai named Shinmen Munisai, who was an accomplished swordsman and an expert in kenjutsu (swordmanship) and juttejutsu. Munisai taught kenjutsu and juttejutsu to Musashi at a young age, as was the tradition in samurai families, and the young Musashi showed an early talent for kenjutsu. Shinmen Munisai's father, Hirata Shogen, was a vassal of Lord Shinmen Iga no Kami of Mimasaka Province.