The Hasebe school comprises a group of Yamashiro-based swordsmiths of the mid- period, traditionally said to have resided at Gojo Bomon Inokuma in Kyoto. Although no extant work bears the inscription "resident of Yamashiro Province," recent scholarship now regarded as "most persuasive" holds that the group's original homeland was Yamato, that it achieved full maturity in under the direct influence of the -, and that it finally settled in the capital. The school's two principal figures are Kunishige and Kuninobu, with Kunihira, Munenobu, and Shigenobu constituting the remaining named members. Active contemporaneously with the masters Hiromitsu and Akihiro, the Hasebe group developed a brilliant and flamboyant manner centered on -- the spectacular full-temper technique -- that, together with the lineage, represents one of the major currents of Yamashiro work in the period. Dated examples from the Enbun and Joji eras (1350s-1360s) firmly establish the school's period of peak activity.
The is meticulous in distinguishing Hasebe from its counterpart on several diagnostic grounds. Where work builds its fundamental from and , with a that thrusts upward and returns with a pointed tendency, the Hasebe manner characteristically employs a base of mixed with , over which , , and are freely applied. The is the school's cardinal hallmark: "broadly rounded," its return "tempered down long" in fashion, "connecting into ." A further diagnostic is the appearance of conspicuous tendencies near both the edge side and the back side of the forging -- "something comparatively uncommon in " -- which the counts among the school's distinguishing traits. The is typically mixed with and , tending to stand overall, with thick and ; at its finest the steel possesses an quality, a moist, lustrous clarity. Construction with extremely thin is a consistent hallmark. Within this shared framework, individual hands are distinguishable: Kuninobu's tempering tends toward angular with a (arrow-nock) tendency and vigorous breaking into at the , while Kunishige's range encompasses both the expected masterworks and a calmer -based manner in which shallow still carries the diagnostic long and traces of . Kunihira's works display an "unbroken kinship" with Kuninobu in the handling of the , while Munenobu's faithfully express the school's characteristic thin construction and gentle temper with plentiful .
The Hasebe school's historical significance lies in its role as the principal vehicle through which - aesthetics were transmitted into the Yamashiro forging tradition during the period. Kunishige's oeuvre, encompassing in the canonical Enbun-Joji style, rare examples of "high documentary value," and exceedingly scarce signed displaying "an outstanding, high-ranking - character," demonstrates a range of workmanship that the describes as "overflowing with vigor." Kuninobu's corpus spans two contrasting scale tendencies -- commanding works exceeding one and compact forms in the six-to-seven range -- with the celebrated Atsuta Kuninobu, preserved at Atsuta Jingu, exemplifying the former at its most imposing. Kunihira's rare surviving is valued for its resemblance to the Kuninobu in the Tokyo National Museum collection, while each of Munenobu's extant pieces constitutes precious reference material for the lineage. Across the group, the designation records consistently praise works in which "the characteristic features of the Hasebe school are plainly manifested" -- the notare-based , the diagnostic long , and the -inflected forging that together constitute a technical vocabulary as distinctive as it is accomplished.