was a Japanese swordsman who may have lived during the Azuchi–Momoyama and early Edo periods and is known primarily for the story of his battle with Miyamoto Musashi in 1612, where Sasaki was killed. Although suffering from defeat as well as death at the hands of Musashi, he is a revered and respected warrior in Japanese history and culture. Later Miyamoto proclaimed that Sasaki Kojirō was the strongest opponent he faced in his life. History Sasaki Kojirō went by the fighting name of , which was also the name of the kenjutsu school he had founded. It is said that Sasaki studied the Chūjō-ryu of sword fighting from either Kanemaki Jisai or Toda Seigen. Toda Seigen was a master of the kodachi. If Sasaki had indeed learned Chūjō-ryu from Seigen, he would have been his master's sparring partner. Due to his master's use of the kodachi, Sasaki used a nodachi, or a long katana, against him, therefore eventually excelling in its use. It was after defeating his master's younger brother that he left and founded the Ganryū. The first reliable account of his life states that in 1610, because of the fame of his school and his many successful duels, including once in the late 1500s when he fended off three opponents with a tessen, Sasaki was honored by Lord Hosokawa Tadaoki as the chief weapons master of the Hosokawa fief in the north of Kyūshū. Sasaki later became skilled in wielding a nodachi, and used one he called monohoshizao ("The Laundry-Drying Pole") as his strongest main weapon. Duel with Miyamoto Musashi Sasaki was a long-time rival of Miyamoto Musashi, and is considered the most challenging opponent Musashi ever faced. There are a number of accounts of the duel, varying in most details except the essentials, such as Kojirō's defeat. The age of Kojirō is especially uncertain – the Nitenki says that during his childhood, he The Nitenkis account initially seems trustworthy, until it goes on to give the age of Sasaki at the time of the duel as 18 years old; it is known that two years earlier he had been a head weapons master for a fief – but then that would imply he had reached such a position at the age of 16, which is extremely improbable. A further complication is that Toda Seigen died in the 1590s. This unreliability of the sources means Sasaki's age could