Niten Ichi-ryu, a Japanese martial art, was established in the early 17th century under the guidance of the illustrious swordsman Miyamoto Musashi. The eponymous designation "Niten Ichi-ryu" signifies "Two Heavens as One School" and pertains to Musashi's distinctive method of wielding two swords simultaneously, namely a wakizashi (short blade) and a katana (long sword).

Musashi considered the simultaneous use of both swords to be a defining characteristic of Niten Ichi-ryu, as it conferred a strategic advantage in combat. Swordsmanship in this style is characterized by an emphasis on fluidity of motion, adaptability, and efficacy.

Niten Ichi-ryu encompasses a multitude of offensive and defensive techniques, such as parrying, counterattacking, and striking. Moreover, Niten Ichi-ryu philosophy encompasses principles of self-discipline, mental concentration, and personal growth, in addition to physical combat.

Presently, martial artists across the globe persist in honing Niten Ichi-ryu, and its enduring influence persists in the domains of Japanese swordsmanship and martial arts at large. .