Two fix Norinaga in time with a precision rare for a medieval smith: one dated Bunpo 3 (1319) adds his age of forty-eight, another dated Ryakuo 3 (1340) his age of sixty-nine, and from these the published sources compute a birth in Bun'ei 9 (1272). An of Ryakuo 1 (1338) supplies a third date, and a Gentoku date is recorded in the Kozan . He worked at Shikkake in Yamato, one of the five lineages of the province beside Senjuin, , Hosho and , and the published record opens text after text with the sentence: the Shikkake school "flourished with Norinaga as its de facto founder" (則長を事実上の祖として栄えた). The registers name his father Norihiro as the founder, but no authenticated work of Norihiro survives, and the papers settle the school on the son. The name itself continued from the end of the period through the period, carried by successors whose separation, the writes, remains an open question.
His hand is among the most readily named in Yamato. The published formula first gives the school the shared frame of the tradition, a high with a wide , an forging with a flowing tendency, and a fundamentally of , and then states the tell: the distinction lies in tempering small strung in series within the (刃中に小互の目を連れて焼く点に特色). One text raises this to a ranking: "among the works of the five Yamato schools, those in which the stand out most are the works of the Shikkake school, and among them the most technically accomplished is Norinaga" (最も技術の優れているものが則長). On his classic blades the strung runs from base to tip. The edge frays into , and ; sits thick, at times rough above the ; and sweep through. The is and strongly swept with , closing or with a feeling, on one blade becoming flame-like. The sources add a quieter mark, that "the subdued tendency of the is also a point not to be overlooked" (匂口の沈みごころの点も見のがせない).
The beneath this temper is an that flows overall and leans to , thick in with fine , in places standing. On the finest blades a clear rises, and one shows steel that runs slightly blackish. The of the twenty-fourth session is described in terms the sources reserve for his best work: a densely packed , bright in iron color and well refined, on which the band of adheres thickly, "beautifully luminous, bright and penetratingly clear" (光美しい刃沸が厚くついて明るく冴え渡り). The strength of that steel is itself a discriminator within the school: the Jubi handed down from Tokugawa Yorinobu is singled out because "the is stronger than usual Shikkake work, and the in the is also stronger" (常の尻懸より地鉄が強く、刃中の沸も強い).
His work falls into clear registers. With Kanenaga he is the Yamato smith of comparatively many signed works, the long taking the forms Yamato Norinaga , Yamato Shikkake-ju Norinaga and Yamato Sakon-no-jo Norinaga , and the sources note that "among those judged the first generation there are no two-character signatures" (初代と鑑せられるものに二字銘はない). His mostly survive with the signature left near the tip on the side, while the are with the long at center; twenty-five of his designated blades are signed against twelve unsigned. The register carries the seals of the Honami: a of Koshitsu, whose inlaid attributions are called extremely few, a of Kojo with an of Tenna 3 (1683) at twenty , kinpun and attributions of Koson, and a lost of 'ei 12 (1635) read as the hand of Koshitsu or Koon. The formula itself reserves a further register, works in pure : a naoshi that once bore an old attribution to Sairen, the quiet of Ryakuo 1 made at sixty-six, and the of Ryakuo 3 at sixty-nine, on which the strung can scarcely be seen. The pole arms are a school specialty; the Ryakuo 1 survives with an inscription the sources call precious as a document, the rest were shortened into , and on them the with its companion is "powerfully cut" (薙刀樋に添樋も力強く), showing the character of Yamato carving. The generations remain unsettled. The old rule reads without the Shikkake prefix as the first generation and prefixed long as the second and after, takes the Sakon-no-jo signature as a second generation around Ryakuo, and the registers give a third at Oei and a fourth at Eikyo. Yet the of the forty-seventh session, dated Ryakuo 3 at sixty-nine and still signed with the prefix, makes the judges hesitate before that rule, and they call it "precious material urging further examination of the generational division" (則長の代別について、さらなる検討を促す貴重な資料). An early successor signs the Kasuga dedication at sixty-two.
The published sources place him by his neighbors. Against , the old connoisseur text quoted in the ninth session warns that Shikkake work is mostly a temper easily confused with , "but the is not as tight as 's and the is thinner, and by the inferiority of rank one should know it as Shikkake" (当麻ほどは地つまらずしてしほ相うすく、位のおとるを以て尻懸と知べし). Against the rank is stated plainly: his "technique is second to Kanenaga" (技術も手掻包永につぐものがある), and the differences are itemized, that his forging stands more in the and falls short of Kanenaga's clarity (則長の方が鍛が肌立つて冴えが足りず), that the stands out far more in his , and that Kanenaga signs only with two characters while Norinaga leaves long . What Kanenaga is to , then, Norinaga is to Shikkake: the smith on whom the school's technique and its signed record both rest, distinguished from every other Yamato hand by the strung in a frame.
He is Jo in Fujishiro's grading, with forty-six designated works on record. Five are Important Cultural Properties, patrimony preserved outside the market; beneath them stand six and thirty , thirty-six blades across the two tiers, with three more on the Bijutsuhin rolls. Twelve blades carry recorded provenance through the great houses: a of the former shogunal collection, recorded as a gift of the tenth shogun Ieharu in 1774 and later held by Tokugawa Iesato; the granted by shogun Tsunayoshi in Genroku 11 (1698) to Matsudaira Yoshiyuki, founder of the Takasu branch, and handed down in that house; the rare Sakon-no-jo transmitted in the Maeda house of with its ; the kept as the sword of Tokugawa Yorinobu of , treasured by its later owner as a with the shogunal ; a formerly of the Mori house; and a gold inlay recording the possession of Honda Nakatsukasa Shoyu Tadakoku. The Date family and the Imperial Family also appear among recorded owners. Of recorded whereabouts today, examples rest with Jingu, the Tokyo and Kyoto National Museums, Seikado Bunko, the Kurokawa Research Institute and the Museum of Fine Arts, Boston. For the collector the arithmetic is sober: most of the and blades are held rather than traded, and an attributed with the strung appears on the market only from time to time. A signed piece, of which roughly two dozen are designated and many sit in institutions or long-held collections, is a genuine rarity, and a dated one is rarer still.