The Unshū grouping gathers smiths of Izumo province (Unshū), and the blades carrying this attribution do not form one continuous lineage so much as two widely separated moments in the province's work. The earlier is Unshū Tadazane, a signed placed around the Eishō era (1504 to 1521) in the late period. The later is Takahashi Naganobu, also recorded as Unshū Naganobu and Takahashi Rihei, a late- smith dated by his own inscriptions to Ansei 3 (1856) and Man'en 1 (1860). Naganobu styled himself the seventeenth-generation successor of Wakasa Fuyuhiro; around the close of the Tenpō era he went to and studied under Chōunsai Tsunatoshi, and after gaining recognition he served as a retained smith (kakae-kō) of the Matsudaira house of Matsue in Unshū until his death in Meiji 12 (1879). Because the two hands belong to different centuries and different stylistic worlds, the group reads as a provincial wakimono gathering rather than a school of fixed transmission.
Across these blades the shared ground is a tightly forged with adhering, after which the two hands diverge. Tadazane's packs closely and flows toward the edge with mixed in, carrying a wide mingled with small , and entering well, and , and a subdued () ; his runs straight to with a long , and the overall effect was read by the as sharing features with the smiths Kiyomitsu and Tadamitsu. Naganobu instead builds bold, long of wide with little taper, his often taking on an almost plain () look with abundant . His preferred temper is neatly aligned mixed with in , though one of his hardens a flamboyant of round heads with a deep, bright and . The most reliable signpost to his hand lies in the : reverse filemarks with , named in the as a characteristic feature.
For the group resolves to its named smiths rather than a collective signature. Tadazane is recognized by his -leaning - and subdued , his example preserved with a -style shuhen-nuri . Naganobu is identified through his reverse tang finishing, his Tsunatoshi-derived , and on occasion a vigorous whose assertive spirit the likens to superior works of the Yamaura lineage; his commissioned blade names Tomono Shigenari of the Matsujō domain and records its making at Kōji Street in the eastern capital. The standing of the group rests on these two distinct workmanships, each documented within the records of its own province.