According to Daitō-ryū's initial history, Yoshimitsu dissected the corpses of men killed in battle, and studied them for the purpose of learning vital point striking (kyusho-jitsu) and joint lock techniques.

Daitō-ryū takes its name from that of a mansion that Yoshimitsu lived in as a child, called "Daitō", in Ōmi Province (modern-day Shiga Prefecture).

For military service during the Later Three-Year War (1083–1089), Yoshimitsu was made Governor of Kai Province (modern-day Yamanashi Prefecture), where he settled.

Legend states it was given by Emperor Go-Reizei to Minamoto no Yoshimitsu and has been treated as a family treasure by the Takeda clan for the past 1,000 years,[1] and at least it is older than 16th century.

According to them, the name "Daito-ryu" originated about 900 years ago from Shinra Saburo Minamoto Yoshimitsu (1045-1127), who could be considered the school's distant ancestor.

The Kojiki, one of Japan's oldest books, tells the story of Takemikazuchi-no-Kami taking Takeminakata-no-Kami's hand and "grabbing it as if it were a reed and throwing it with his sword."

Yoshimitsu gave his second son, Yoshikiyo, the flag and armor Shieldless [ja] handed down from the Minamoto clan and made him his successor.