Yoshihiro was a native of Matsukura no Go in Etchu province (Toyama Prefecture). He is said to have studied with or under Masamune in Kamakura, and must have been close to Norishige of Etchu, said to also have been a pupil of Masamune. The 1719 Kyoho meibutsu cho (Catalogue of famous things [swords in shogun and daimyo collections] compiled in the Kyoho era) lists seven blades by Yoshihiro of which five are today designated either Kokuho (National Treasure) or Juyo Bunkazai (Important Cultural Property).
This sword is the only known piece attributed to Go no Yoshihiro in its unaltered original length. With the characteristic jihada and hamon of Yoshihiro, the original shape with the koshizori curve suggests an earlier date than is usually given for work by this smith. A vermillion lacquer attribution to Yoshihiro by the nineteenth-century sword polisher and appraiser Hon'ami Nagane is no longer discernable on the tang. A small triangular sword-cut on the mune about 9 cm from the machi tells of the use of the sword in combat past.
The Kyoho meibutsucho records eleven swords by Yoshihiro, none signed. The same document ranks Yoshihiro with Awataguchi Yoshimitsu and Masamune as the "Sansaku," or "Three Great Smiths," showing that although no signature was known for Yoshihiro, his blades were defining signature enough for the connoisseurs of the day. It is not surprising that after the publication of Kyoho meibutsu cho the three hundred or so daimyo each would have aspired to possess at least one work by the "Sansaku," of which there were but few by Yoshihiro, leading to the saying "You will never see a changeling or a 'Go'."
The 1607 Kaifunki ranks Yoshihiro "as skilful as Masamune and not beneath him." In fact, the work of Yoshihiro is different from that of both Masamune and Sadamune, and in many ways more refined. The outstanding feature of the blades is the clarity and brilliance of the jigane, very much in evidence on this blade. While the activity within the hamon of Masamune's work is prominent and almost violent, that on the work of Yoshihiro seems an essentially deeper part of the whole composition of ji and ha. This sword is nothing less than a masterpiece.