The Hasebe school represents one of the principal sword-forging lineages of Yamashiro Province during the period, flourishing contemporaneously with the celebrated () masters Hiromitsu and Akihiro. Traditional accounts place the Hasebe smiths at Gojō Bōmon Inokuma in Kyōto, yet no extant signed works bear the inscription "resident of Yamashiro Province" (Yamashiro no jū). Recent scholarship has advanced the view—now widely regarded as most persuasive—that this group originally came from Yamato, achieved full maturity in , and ultimately settled in Kyōto. The best-known representatives of the lineage are the brothers Kunishige and Kuninobu, with other documented smiths including Kunihira, Munenobu, and Shigenobu. The Kōsei records that Kuninobu was the son of the first-generation Kunishige and the younger brother of the second-generation Kunishige.
The Hasebe school is particularly celebrated for its mastery of the flamboyant (all-over temper) style that emerged in this period, characterized by , , and frequent that combine to create a brilliant, fully-tempered appearance. Whereas typically employs a foundational pattern centered on and , the Hasebe approach fundamentally relies on mixed with as the underlying structure, upon which the spectacular effects are built. The forging displays another distinctive feature: a conspicuous tendency toward grain near the edge and ridge—an element not especially prominent in mainstream work. The typically shows flowing mixed with and sometimes , accompanied by thickly adhering and abundant , producing a hard, vigorous steel. The is characteristically wide () and richly varied, with deep , thick , and frequent and that flash through the temper. The often features a rounded () or pointed turnback with , and blades frequently display deep tempering that becomes -like.
Works attributed to the Hasebe school are noted for their bold, imposing proportions—broad with little taper from base to tip, shallow , and —features that exemplify the distinctive martial character (jidai-shoku) of the mid- period. Signed works in form are exceedingly rare, while comparatively more and survive. The natural quality of the and —neither contrived nor ostentatious—deepens the aesthetic appeal of these blades. Among Hasebe attributions, works showing particularly strong , tall temper rising to or crossing the , and indomitable spirit in the are esteemed as exceptional examples. The lineage, together with the group, stands as a representative presence among Yamashiro smiths of the era, and their vigorous, varied tempering continues to be admired for displaying both technical brilliance and martial vitality.