Kunikane of Sendai was the founding smith of a lineage retained by the Date clan of Oshu. The first generation, born in Bunroku 1 (1592) at Kokubun Wakabayashi in Miyagi District, was known by the name Hongo Genzo and later Yoshinosuke. He styled himself a later offshoot of the Yamato Hosho Goro lineage and, by his lord Date Masamune's command, traveled to Kyoto in Keicho 19 (1614) to study under Etchu no Kami Masatoshi. He received the title Yamashiro Daijo in Kan'ei 3 (1626), and upon Masamune's death in Kan'ei 13 (1636) took the tonsure as Nisawa Yoe, yet continued forging until his death in Kanbun 4 (1664) at the age of seventy-three. His eldest son, Hongo Kichiemon, succeeded as the second generation in Shoho 2 (1645) and received the title Yamashiro no Kami in Kanbun 7 (1667); he died in Kanbun 12 (1672) at the age of sixty-one. The NBTHK consistently describes the second generation as a smith "of high skill, following his father," whose works at their best "approach the first generation in quality" and are "scarcely inferior to that of the first generation."

Both generations worked consistently within "the family's traditional specialty: the Yamato Hosho tradition." The defining technical character is a masame-hada forging, tightly packed and well ordered, with thick ji-nie and fine chikei. The hamon is a suguha-based temper -- typically chu-suguha carrying a shallow notare feeling -- in which hotsure appears frequently along the habuchi, often intertwining into the ji to produce a nijuba-like aspect. Kuichigai-ba is mixed in, and sunagashi and kinsuji enter along the hardened edge. The boshi characteristically runs straight with hakikake, tending toward yakizume. A rising mizukage appearing below the hamachi is noted as "a characteristic habit seen in the second generation as well as the first." The nioiguchi is repeatedly described as "bright and clear." Among the second generation's works, examples in gunome-midare are also encountered, though the suguha mode predominates. The tang file marks rendered as simple kesho are identified as "among the points of interest in his work," while the signature calligraphy -- with horizontal strokes finished with a strong pressing down and a distinctive rendering of the character element within kane -- is cited as "an important feature for appraisal."

The NBTHK appraises the Kunikane lineage as "a leading figure among the shinto swordsmiths of Oshu" whose craft "successfully inherited the manner of Hosho" and "successfully recreates the Hosho tradition of Yamato." Individual works are praised as displaying "refined elegance and a quiet warmth," possessing "many points of appreciation while retaining an archaic flavor," and presenting "a bold and imposing sugata." The finest blades are characterized as "extremely meticulous" and executed "with great care," showing "no shortcomings." Dated examples are singled out as "precious as documentary material" and "valuable source material" for understanding the development of the lineage's style. The presence of cutting-test inscriptions by Yamano Ka'emon is noted as rare and of particular interest. Taken together, the Kunikane line represents a faithful perpetuation of the Yamato-den within the shinto period -- smiths whose disciplined adherence to Hosho forging methods and suguha tempering produced works of scholarly distinction and enduring institutional regard.