Yukihide (左行秀) was born in Bunka 10 (1813) in the Hoshimaru area of Asakura, Kamiza District, Province, the legitimate son of Matabei Morishige. The record that he styled himself the thirty-ninth-generation successor to the () line, and that he carved this claim into the inscriptions of certain blades, which is the source of the name borne by his work. In the early Tenpō era he went up to and studied forging under Shimizu Hisayoshi, a disciple of Hosokawa Masayoshi. In Kōka 3 (1846), at the age of thirty-four, he went down to Tosa on the recommendation of Sekita Shinpei Katsuhiro, a swordsmith in the service of the Tosa domain, and in the tenth month of Ansei 2 (1855) he became an official Tosa domain smith. From the close of Man'en 1 (1860) into the early part of Bunkyū 2 (1862) he again went up to , establishing a residence and forging at the Tosa domain estate at Sunamura in Fukagawa. After discord with Itagaki Taisuke in Keiō 3 (1867) he returned to Tosa and thereafter signed "Tōko." His swordmaking concluded in Meiji 3 (1870), and he spent his later years in Yokohama with his heir Ikuma until his death in Meiji 20 (1887), placing the school's production squarely in the mid-nineteenth century revival of the Sōshū-den.
Across the register, the shared vocabulary is consistent enough to function as a recognition key. The is bold and weighty: a wide with little taper, thick , frequent , and an (a slightly more slender, form with an extended appears in the Tosa and -residence pieces). The is a densely forged that often flows toward , sometimes predominantly , carrying thick fine and abundant over notably clear steel. His favored , named repeatedly as the manner he most excelled in, is a or base bearing a shallow tendency intermixed with and , with and ; the is conspicuously deep, adheres thickly with occasional coarse grains, and , , and run through a bright, clear edge. The is or turning back in with . A vigorous in Sōshū-den coloration, understood as aiming toward the manner of Gō Yoshihiro, appears in a and in a rare . The is with and bold, deeply cut signatures, frequently raising the place characters "Chikushū" or "Doshū" and recording the forging site or iron used. Beyond the school itself, no pupils are named in these blades; the carver Isogai Yoshitatsu, a disciple of Masayoshi, executed the on the , a fact noted on its tang by Myōchin Ki Muneteru.
For , the deep with thick, brilliantly bursting over a clear -tending ground is the firmest discriminator, with localized tightening of the noted as an appealing departure from his usual breadth. The single out documentary inscriptions: the place-name "Ōshima-sanroku" recording the forging locale, and his repeated use of Nambu mochi-tetsu iron from the Kamaishi area, a material also employed by Unju Korekazu, Tairyūsai Munenobu, Iwai Masatoshi, and Gassan Sadakazu. The Meiji 3 carries the latest confirmed date and shows the shorter, period-marked form of his closing years, distinct from the grand Ka'ei and Ansei works. A fully matched is recorded as exceptionally uncommon. Jūyō-Bijutsuhin pieces in the register were published in Meitō Shūbi, Meisakushū, Nihontō Taikan, and Kanzan Tōwa. The present Yukihide as a leading hand of the Bakumatsu revival, his strongest blades carrying the school's claim to the medieval name into a forceful late- idiom.