Nobunaga is recorded in the published sources as a smith of the Yamato Taima school who, at the start of the Muromachi period, removed to Asako in Echizen, where the same name continued for several generations under the collective title Asako Taima. The Taima group was one of the five Yamato traditions, the temple smiths of Taima-dera, and Nobunaga carried its masame-leaning steel and nie-laden temper north into Hokuriku. There the work took on a second character. The published commentary on a tanto designated in 2023 names it outright, finding in the forging both the steel of the Hokuriku makers and the temperament of Yamato, 「北陸物の特徴と大和気質が看取される」[[c:1]]. His prime years are placed around the Oei era, and the designated record gathers six blades, all signed with a bold two-character 信長 and overwhelmingly tanto, so that he is known less as one documented hand than as the manner of a northern Taima line held across generations.
The make that most distinguishes his work is an angular gunome-midare. The published sources fix it in a single repeated sentence, that his style resembles the Fujishima line of Echizen and Kaga, 「藤島一派に似て」, with an angular gunome predominating, 「角ばる互の目乱れが多く」[[c:2]], and they say so again of the Kashu Fujishima manner with the same words, 「角張る互の目乱れが多く」[[c:3]]. The square-shouldered teeth run linked together with ko-notare and small gunome, and the habuchi frays as it goes, hotsure and nijuba opening along the edge while sunagashi sweeps the ha and kinsuji enter. On a tanto of the twenty-fourth session the same hand works gunome mixed with ko-notare, the nie thick, the sunagashi and kinsuji frequent, and the published sources call it a superior work of the smith, 「同工の優れた作である」[[c:4]]. The boshi is the school's other tell, most often brushed into hakikake, 「帽子は掃きかけていることが多い」[[c:5]], turning back ko-maru or to a point.
Under this temper lies a forging that reads two ways at once. It is an itame mixed with mokume and a flowing nagare-hada, standing open rather than tight, the ji-nie gathering well and chikei entering, the steel inclining to a darkened tone the commentary calls kane-black. That standing, blackish jigane is the Hokuriku side of the inheritance, while the masame-gokoro mixed near edge and ridge and the quiet nie of the suguha pieces keep the Yamato side visible. A kodachi of the twenty-fifth session adds a faint shirake-utsuri rising over the ji and a habuchi leaning saka on the lower ura, a touch of the misty old reflection on otherwise northern steel. The tanto of the sixty-ninth session sets the whole jigane out at its most open, the grain standing with mokume and nagare and the kane darkening, and it is on that blade that the published sources read the Hokuriku character and the Yamato temperament together.
Against the angular standard the published sources mark a quieter register, noting that suguha and shallow notare are also among the work. A tanto of the twenty-second session is a chu-suguha, the nioiguchi drawn tight with ko-nie and a touch of yakikomi near the machi, well forged and sound, the school in its calm key. A wakizashi of the twenty-fourth session takes a shallow notare instead, laid with hotsure, nijuba, frequent sunagashi and kinsuji, and the commentary singles out exactly this manner as the very feature of the smith, that the blade tempers a notare ha and shows Nobunaga's character, 「のたれの刃を焼いて信長の特色をみせ」[[c:6]]. The two registers are not finally separate, and the latest tanto proves it: katakiriba on the omote, hira-zukuri on the ura, its omote breaking into a boxed gunome with a suggestion of choji while its ura runs a shallow notare, a single blade in which two manners are shown at once, 「一口で二様の作域が示された」[[c:7]]. Because not one of the six is dated, this manner-reading is how the line is ordered, the kodachi judged not to fall below early Muromachi serving as the chief anchor.
What sets Nobunaga apart is best drawn from his own grounded traits rather than from his model. The resemblance to Fujishima is real and the sources insist on it, but the discriminators are the angular gunome run linked with a frayed habuchi, the standing dark steel that turns kane-black, and the hakikake boshi, the cluster that marks a northern Taima blade and separates it from the tighter Yamashiro-leaning suguha of the parent Taima at home. A same-name smith worked in Kaga, and the published sources are careful to keep the two apart, recording that the relationship between them is not clear. The signature itself is part of the kantei: all six designated blades carry the two-character 信長, four on ubu nakago and two shortened, the form almost always tanto, and the commentary observes that genuinely signed long pieces are uncommon, 「信長有銘の作品はめずらしく」[[c:8]].
The designated record runs to six blades, all of them in the Juyo tier and none raised to the higher designations above it, and the toko-taikan valuation sits in the middle of the field, so Nobunaga is a connoisseur's name rather than a headline one. His standing rests instead on a single celebrated mounting. The kodachi of the twenty-fifth session is housed in a Higo koshirae copied faithfully after the Nobunaga mounting once held by Hosokawa Sansai, the blade within a shortened but genuinely two-character-signed tachi that the published sources praise for showing the period color of early Muromachi well, 「室町初期の時代色をよく示した」[[c:9]], and they prize it the more because his signed long work is so rare. Provenance is otherwise thin in his record, the Sansai association the one firmly grounded thread. For a private collector the practical picture follows from the numbers: the surviving designated pieces sit in the Juyo and lower tiers rather than locked away as cultural property, so an Asako Taima tanto is not beyond reach, but only a handful are on record and one comes to market rarely, a signed long blade rarer still, so that meeting one is a matter of patience.
