The Nagato school carries the manner westward, out of its home and into the province of Nagato (the territory the smiths name in their signatures as Choshu). Its origin is a single relocation: Yasuyoshi, the son of O- and second generation of the line, is traditionally said to have moved from to Choshu, an account anchored by an extant dated Shohei 17 (1362) inscribed Choshu-ju Yasuyoshi. From him the name passed down through the late and into the early period, the descendants and students who continued it gathered under the collective reading "Choshu ." Akikuni is the chief of those continuators, transmitted as a disciple taken on after Yasuyoshi carried the name into the province; the reference works on signatures list six smiths who bore the Akikuni name, beginning with a Bunwa-era hand of the Yasuyoshi line and reaching to an Oei-period smith described as the son of Choshu Yasuyoshi, so that the name is best read as one handed down through the Nagato workshop. The school is therefore a provincial, late branch of the tradition, working a country forge in an old manner whose dated examples run from the Shohei and Eiwa years through Oei and into Bunan.
In the forge the members describe a common vocabulary. The is mixed with and , the grain often standing toward , with thick and fine -like lines of steel; a whitish is named as a hallmark, and the ground steel frequently shows a somewhat dark, iron-like tone rather than the bright . The divides into a quieter mode and a representative manner: shallow mixed with , the running linked in a connected pattern the smiths call , with and entering, adhering, and fine and drawn through; the temper is mainly -dominant with the tending to sink. The enters with a pointed tendency and a long , at times a swept in . Within this shared frame the members diverge by degree: Yasuyoshi's finest pieces forge compact and bright, retaining the school's character most clearly, while Akikuni's run coarser and more -driven, his broadest carrying a rustic (yashu) cast and, with a large , a vigorous and commanding spirit.
To a Nagato , read the school against its source. The consistently note that the work does not match O- in the brilliance of both and temper; the standing grain, the , the darker steel and the sinking mark the peripheral western forge, and the manner sometimes does not connect directly to Yasuyoshi's own style, the attribution resting on a transmitted current of workmanship rather than a close stylistic tie. Signed works are comparatively few, which lends the surviving inscriptions particular documentary value: a date and a place-name (Choshu-ju Yasuyoshi, or Choshu Setozaki junin Akikuni, sometimes with the title Saemon no Jo, sometimes folded over as an ) do as much to anchor a piece as the temper, the more so because several Akikuni share the one name. Yasuyoshi is the senior hand of the group, his larger and more imposing than his father's with wide and thin ; Akikuni follows as a well-documented branch smith, graded jo , whose large-scale blades are scarce and valuable for fixing the chronology of production. Provenance, where it survives, reads like the local history of the blade: Yasuyoshi's work descended in the Inshu Ikeda and Maeda houses, and Akikuni's in the Ouchi of Suo and Nagato and the Mori who succeeded them, the western great houses keeping the western to themselves.