The Shimada school (島田) took its name from its base in Suruga Province, where it worked from the mid- period along the Tōkaidō between the hearths and the late smiths of neighboring . The published sources place its founding generation in the Kōshō (or Kyōshō) era and trace its principal names without interruption down into the period, with the names continuing as late as the era. Three smiths stand as the school's central hands: Yoshisuke (義助), held to be the principal mainstream name at the head of all Shimada work; Sukemune (助宗), recorded as the younger brother of the founder; and Hirosuke (廣助), placed as the son of the second-generation Yoshisuke. The oldest extant dated example, an Eishō 2 (1505) by Yoshisuke, fixes the early corpus, and because the signature style does not separate the hands, a signed Shimada blade is read for its workmanship rather than assigned a generation. The Shimada smiths produced the working blades of the century; one Hirosuke , a Kōshū-uchi work dated Eiroku 2 (1559), was held by Hara Nyūdō Toratane of the Twenty-Four Generals of the Takeda, and the cut struck into the at the of a Yoshisuke drew a remark that it speaks to martial use.
Across the members the school reads in a single - idiom inflected by and . The the smiths describe is an , well knit and at times dense, that flows and leans toward , standing somewhat open in , with fine lying through it, entering, and a tonality the commentaries repeatedly call whitish; this flowing, slightly standing steel, rather than a tight surface, is what marks the Shimada hand for the eye. Upon it the smiths set a crossed with , with and pointed entering, , abundant , and and running through, the commonly turning back rounded, at times with ; and slight appear, and on the larger blades the activity rises toward in . Sukemune's particular register is the connected the names the school's hallmark, while Hirosuke shows the most robust make, favoring a wide with and an extended . Against this typical every hand keeps a quieter exception: a the commentary calls comparatively uncommon for Yoshisuke, and a mixed with small on a Sukemune read as made with an eye toward the manner of . The carving tradition is shared throughout, , , , relief , and the figures of and Fudō Myōō, with openwork noted by examiners as an uncommon thing to find; the school also produced comparatively many , Yoshisuke's ōmi- among them.
To a Shimada blade is to read the late idiom in a provincial Suruga register: the whitish, standing beneath a -laden with , , and frequent , set apart from a tight and tied by the published sources to Sue-Sōshū, late Seki, the Senju group, and the work of and . Form sorts the manner: the broad -leaning on one side, the school's and (often with , thick , and a withered ) on the other. Among the members Yoshisuke is the name the sources reach for in describing the group, his finest and praised for a and of clear, bright result; Sukemune's Osaka is judged his finest work; and Hirosuke's best pieces, one called , the best among its kind, with a suggestion he privately emulated Chōgi, number among the finest of the whole lineage. Dated and fully signed works such as those inscribed Shimada Hirosuke are particularly valued, the tangs anchoring the chronology of the later generations, and a rare collaborative blade between Hirosuke and Gensuke attests to the collegial working of the shop. Provenance reaches to the Imperial Family, which has held works by Yoshisuke, Sukemune, and Hirosuke; with the Takeda general's blade and the documentary dated pieces, these holdings mark the standing of a respected one-province school whose hand sits close to the late tradition.