The school (当麻) is one of the five great traditions of Yamato Province, taking its name from -dera, the temple to which its smiths were attached. The lineage was founded by Kuniyuki in the late period and flourished through the era, producing such figures as Aritoshi, Tomokiyo, and Tomoyuki. Their connection to the temple profoundly shaped the school's character: as artisans working under monastic patronage, the smiths produced blades of contemplative restraint, and the temple affiliation is also cited as the principal reason that extant signed works are "exceedingly few" -- a circumstance the emphasizes with remarkable consistency, noting that the great majority of surviving pieces are unsigned blades identified through attribution. Beyond the Yamato heartland, the school's influence extended into the provinces: Nobunaga, a later smith, relocated to Asako in during the early period, establishing the line known as "Asako " and carrying the school's Yamato temperament into the Hokuriku region.
The collective technical identity of the school rests on a -based tempering idiom of extraordinary internal richness, executed within the structural framework that defines craftsmanship -- wide , high , and pronounced tendency in the forging. Kuniyuki's is a well-worked mixed with , with thick and throughout; his is gently and mixed with or small , with along the , frequent and , and a tending toward ending in . These foundational traits recur across the school's members with individual inflection: Aritoshi intensifies the diagnostic , uchi-noke, and to a degree that "stands out even among works," producing what the calls "an individualistic manner" within the shared idiom, with of particular brilliance. Tomokiyo's -period constructions display wider and more vigorous , while Tomoyuki's works introduce and mixing into the base, with conspicuous in the finest examples. Nobunaga's production adds a distinctive angular -- the hallmark of the Asako variant -- alongside a somewhat darkened steel tone reflecting Hokuriku workmanship. Throughout, the is bright and clear, and the steel is consistently praised for its luminous quality.
The school's enduring significance within the Yamato tradition lies in its refined synthesis of monastic restraint and internal dynamism. Beneath what the describes as an overall "subdued () impression," the school's blades harbor an abundance of scenic effects -- , , , , , uchi-noke -- that reward close and sustained observation. Kuniyuki's role as the defining voice of the tradition is affirmed by the rarity and quality of his signed works, which demonstrate the "bright and clear" (akaruku ) character of and that subsequent generations would carry forward. Aritoshi's luminous serves as the primary attribution criterion for the school's finest unsigned blades. Tomokiyo and Tomoyuki preserved the idiom through the period in constructions of imposing scale, while Nobunaga's provincial migration demonstrates the tradition's resilience and adaptability. The 's consistent assessment -- that blades possess "a deeply flavored and engaging style" conveying dignity, contemplation, and the essential character of Yamato craftsmanship -- secures the school's honored place among the five great traditions of the province.