Among the provincial lines that carried the Kyoto manner beyond Yamashiro, the (延寿) school of province grew up at Kumafu in the Kikuchi District, working from the close of the period through the era. Its founder, Tarō Kunimura, is transmitted in the prevailing account as the son of Hiromura of the Yamato Senjuin line, who married a daughter of Kuniyuki of Yamashiro; by that marriage Kunimura is held to be Kuniyuki's grandson in the female line and a pupil of the workshop (one early text instead places him in the gate of Kunitoshi). The school name reads on the characters as the line itself, and from that double descent, Yamashiro through the marriage and Yamato through the Senjuin side, the family took its character. Around the founder a cluster of named smiths arose almost at once, Kuniyoshi, Kunitoki, Kuniyasu, Kunitomo, Kunisuke, Kuninobu and Kunitsuna among them, the line attached to the Kikuchi clan and loyal to the Southern Court, so that the dated blades carry that history in their Southern-Court eras.
The published sources describe work as one that broadly resembles the school, refined in yet cooler and whiter than its Kyoto parent, and they name the provincial accents by which the two are separated. The forging is an or closely packed that flows toward the edge into , the grain standing a little, with fine laid on and delicate entering; over it rises a whitish , the surest single tell, the cool reflection of a Kyushu steel that is not quite the bright . The temper is a or narrower , the carried somewhat (sunken and quiet), often breaking into , the doubled line that recurs across the line; , , , fine and play within it, the activity gentler than the brighter . The turns back on a larger radius than 's tight , a shallow with a short . The signature is a tool of attribution: across the line the right half within the (国) enclosure is cut in an ear-shaped form, a calligraphic habit the sources say cannot be confused with another school. Against true , the school is read by its -lean, its whitish , its sinking and its quieter internal work, the and running a degree softer than the Yamashiro line.
To an blade is to weigh those provincial accents against the air it carries: a wheel-like wa-zori and Kyoto refinement may recall the parent at a glance, but the in the , the , the subdued and the ear-shaped settle the attribution, and the level of the work then narrows it to a hand. The founder Kunimura sets the quiet register and signs the slender, sharply tapering the sources call distinctive even within the school; among the later smiths, Kunitoki survives in relative number and runs his the busiest with and , Kuniyasu is the most -laden and brightest, Kunisuke cuts the boldest chisel and hardens a unique flaming on his wide pieces, while Kuniyoshi, Kuninobu and the various other - smiths work the vocabulary, the best of them refining the steel to a clarity that escapes the school's whitish thinness. The corpus runs mostly to slender signed and to attributed on appraisal, with broad in the phase, the work confined to long blades in the founder's case. Provenance is unusually grand for a provincial line: blades pass through Toyotomi Hideyoshi and Tokugawa Ieyasu and rest in the Hosokawa, Date, Uesugi, Owari and Mito Tokugawa houses, with examples held today by the Sano, Tokugawa, Seikadō and other institutions. A signed is among the rarer encounters in work; most survive as the attribution, held as heritage rather than offered.