Miyaguchi Toshihiro / Yasuhiro, (1897-1956) also signed Kunimori, was the 3rd generation of Miyaguchi Ikkansai, grandson of Miyaguchi Shigetoshi and belonged to the Ikkansai Mon (school). "MINAMOTO KIYOMARO", was the greatest master of the Shinshinto period and was also of this school. On December 23, 1932 the board of directors of the Yasukuni Shrine (Yasukuni shrine is devoted to the protection, and Memory of "Samurai and Military Warriors") approved the establishment of the "Nihon To Tanren Kaji". Toshihiro was summoned and given the smith name Yasuhiro July 8th, 1933 by the war minister "Araki Sadao". He was then appointed in charge of the Yasukuni Tanren Kai Foundation, and listed as one of its Founders. In 1933 he began producing swords at this well known, and prolific school of sword smiths.  In 1936 he was transferred to become the chief instructor, and Sensei of sword making at the Okura Tanrensho Dojo, founder by Baron Okura Kihachiro; he remained there throughout the WWII period. He worked at the Yasukuni shrine until 1936, producing approximately 500 swords.

When sword making was allowed to re-commence in 1954, Toshihiro applied and obtained a license to produce swords. His skill in sword making, along with his skill in horimono and gold inlay work are still considered superb. Some of his most significant works included: a sword to Emperor Hirohito; a sword donated to the festival commemorating the 700th anniversary of the retired Emperor Gotoba; a Tachi to the Ise Shrine; and the tachi made for the Yasukuni shrine.