Kunimune of Bizen, called Bizen Saburo, worked in the middle Kamakura period, the published sources placing him around the Shogen years (about 1259). He belonged to the Naomune line (直宗系), the third son of Naomune's son Kunizane, and from that birth order he was known as Saburo, the third. He lived at Osafune, yet the published sources keep his line clear of the Osafune mainstream and read his metal as Bizen to the last. The texts also carry an old account of his career: that the regent Hojo Tokiyori summoned him east, where with Sukezane of the Fukuoka-Ichimonji school and Kunitsuna of the Awataguchi school in Kyoto he became one of the pioneers of Sagami swordmaking (相州鍛冶). One Tokubetsu Juyo tachi sets the story down plainly, saying he 'was later summoned by the Kamakura shogunate under Hojo Tokiyori and moved to Kamakura, where together with Sukezane of the same province's Fukuoka-Ichimonji school and Kunitsuna of Kyoto's Awataguchi school he became one of the pioneers of Sagami swordmaking'[[c:1]].

The published sources divide his work into two hands, and that division is the whole of the smith. The first is a wide, powerful tachi, often with high koshizori and funbari and on the finest pieces an ubu pheasant-thigh kijimomo nakago, tempered in a flamboyant choji-led midare. Over an itame mixed with mokume that tends to stand he forges a vivid midare-utsuri, the temper crowding with gunome, angular and pointed teeth, ashi and yo entering richly, nioi-laden with ko-nie, kinsuji and sunagashi working through. The signature feature appears in this hand: the texts say that in the flamboyant midare works there is, as it has been called since old times, the 'Bizen Saburo no shirajimi,' a whitish stain that shows within the ha (古来「備前三郎の白染み」と称して, 刃中に染みがあらわれるところが特色とされている). The same texts add that the stain belongs mainly to this flamboyant hand and is little seen in the quiet one, so that its presence reads as a mark of the maker rather than a flaw.

The jigane is where the published sources set his point of difference. His flamboyant choji recalls Mitsutada and Moriie at first glance, yet beside them his forging stands somewhat more, the ha-hada at times rises, and nie mixes into the ha; ji-nie gathers on the standing itame, fine chikei runs in it, and the midare-utsuri rises bright. In places the nioiguchi sinks and clouds, an urumi the texts read together with the shirajimi as one quality of his steel. Over this hand the boshi runs midare-komi with a pointed tendency, or rises sugu and returns in a small round with brushed hakikake at the tip.

Beside the flamboyant hand stands a quiet one, and the two together are the spine. The second manner is a slender or ordinary-width, gentle sugata, the forging tighter, at times a fine ko-itame with minute ji-nie. Its temper is a suguha-cho mixing ko-choji and ko-gunome, with ashi and slanting saka-ashi, the nioiguchi tight with ko-nie, bright and clear at its best. The texts tie the two manners to the signatures themselves: the flamboyant hand is signed large, with a thick chisel and rounded calligraphy, the quiet hand small, with a thinner chisel and squared calligraphy. This quiet hand carries the dated remains, the late-Kamakura Showa years (正和年紀), and from the breadth of the two manners and those late dates the texts judge that 'taking the change of styles and the chronological evidence together, it appears the name was probably not the work of a single generation, though this point should await further study'[[c:2]].

For recognition the boshi is the working tell in the quiet hand. A calm Kunimune in suguha may look at first like Osafune Sanenaga or Kagemitsu, but the texts mark the difference at the turnback: of one signed tachi they say it 'at first sight recalls the workmanship of Sanenaga or Kagemitsu of Osafune, yet shows a difference in that the boshi rises straight and returns in a large round o-maru'[[c:3]], the slightly nie-laden ji and ha and the prominent chikei completing the judgment. At the flamboyant top end the confusion runs instead toward Ichimonji, and there a koshi-biraki opening in the midare and nie clotting even inside the ha settle the attribution; that koshi-open manner marks the small sub-group of the Tenkyuwari look, an anchor for mumei blades of the same air. The shirajimi too is a keyed feature rather than a constant: the texts note that 'this phenomenon is frequent in the works with a flamboyant midare temper and is little seen in those of a suguha-toned make'[[c:4]]. The lineage is kept clean at the root: the Naomune line stands apart from the Osafune mainline, and Nakahara Kunimune, whose dated tachi run from Kagen to Engyo in a quiet suguha base, is regarded as a pupil of the first generation.

For the connoisseur, Kunimune is Sai-jo saku in Fujishiro's grading, with three National Treasures, ten Important Cultural Properties and eight Tokubetsu Juyo among ninety-seven designated works on record. The National Treasure tachi of Terukuni Jinja in Kagoshima stands at the head of his signed work; the Nikko Toshogu tachi is the National Treasure of his rarer nie-based hand. The named blade Tenkyuwari carries one of the great sword histories: it was the sword Uesugi Kenshin wore when he broke the camp of Takeda Shingen's brother Tenkyu Nobushige at Kawanakajima, was given by Kenshin to Satake Yoshishige, and was held thereafter in the Satake house, lords of Kubota in Dewa, with an itomaki tachi koshirae of Kansei date. The Uesugi, Satake and Shimazu, the Kishu and Owari Tokugawa, the Ii and Abe houses and the Imperial Household appear among his recorded owners, and one tachi reached the Boston Museum of Fine Arts. About sixty-three of his blades fall in the Tokubetsu Juyo and Juyo tiers, which makes a designated Kunimune among the more attainable of the great Kamakura names; the National Treasures and Important Cultural Properties are heritage held in shrines and museums and do not trade, while a Tokubetsu Juyo or Juyo example, most of them held rather than offered, comes to a private collector only with patience, and is a major acquisition when it does, the one realistic way to own the Bizen master whose journey east stands behind the rise of Soshu.

Kunimune of Bizen, called Bizen Saburo, worked in the middle Kamakura period, the published sources placing him around the Shogen years (about 1259). He belonged to the Naomune line (直宗系), the third son of Naomune's son Kunizane, and from that birth order he was known as Saburo, the third. He lived at Osafune, yet the published sources keep his line clear of the Osafune mainstream and read his metal as Bizen to the last. The texts also carry an old account of his career: that the regent Hojo Tokiyori summoned him east, where with Sukezane of the Fukuoka-Ichimonji school and Kunitsuna of the Awataguchi school in Kyoto he became one of the pioneers of Sagami swordmaking (相州鍛冶). One Tokubetsu Juyo tachi sets the story down plainly, saying he 'was later summoned by the Kamakura shogunate under Hojo Tokiyori and moved to Kamakura, where together with Sukezane of the same province's Fukuoka-Ichimonji school and Kunitsuna of Kyoto's Awataguchi school he became one of the pioneers of Sagami swordmaking'[[c:1]].

The published sources divide his work into two hands, and that division is the whole of the smith. The first is a wide, powerful tachi, often with high koshizori and funbari and on the finest pieces an ubu pheasant-thigh kijimomo nakago, tempered in a flamboyant choji-led midare. Over an itame mixed with mokume that tends to stand he forges a vivid midare-utsuri, the temper crowding with gunome, angular and pointed teeth, ashi and yo entering richly, nioi-laden with ko-nie, kinsuji and sunagashi working through. The signature feature appears in this hand: the texts say that in the flamboyant midare works there is, as it has been called since old times, the 'Bizen Saburo no shirajimi,' a whitish stain that shows within the ha (古来「備前三郎の白染み」と称して, 刃中に染みがあらわれるところが特色とされている). The same texts add that the stain belongs mainly to this flamboyant hand and is little seen in the quiet one, so that its presence reads as a mark of the maker rather than a flaw.

The jigane is where the published sources set his point of difference. His flamboyant choji recalls Mitsutada and Moriie at first glance, yet beside them his forging stands somewhat more, the ha-hada at times rises, and nie mixes into the ha; ji-nie gathers on the standing itame, fine chikei runs in it, and the midare-utsuri rises bright. In places the nioiguchi sinks and clouds, an urumi the texts read together with the shirajimi as one quality of his steel. Over this hand the boshi runs midare-komi with a pointed tendency, or rises sugu and returns in a small round with brushed hakikake at the tip.

Beside the flamboyant hand stands a quiet one, and the two together are the spine. The second manner is a slender or ordinary-width, gentle sugata, the forging tighter, at times a fine ko-itame with minute ji-nie. Its temper is a suguha-cho mixing ko-choji and ko-gunome, with ashi and slanting saka-ashi, the nioiguchi tight with ko-nie, bright and clear at its best. The texts tie the two manners to the signatures themselves: the flamboyant hand is signed large, with a thick chisel and rounded calligraphy, the quiet hand small, with a thinner chisel and squared calligraphy. This quiet hand carries the dated remains, the late-Kamakura Showa years (正和年紀), and from the breadth of the two manners and those late dates the texts judge that 'taking the change of styles and the chronological evidence together, it appears the name was probably not the work of a single generation, though this point should await further study'[[c:2]].

For recognition the boshi is the working tell in the quiet hand. A calm Kunimune in suguha may look at first like Osafune Sanenaga or Kagemitsu, but the texts mark the difference at the turnback: of one signed tachi they say it 'at first sight recalls the workmanship of Sanenaga or Kagemitsu of Osafune, yet shows a difference in that the boshi rises straight and returns in a large round o-maru'[[c:3]], the slightly nie-laden ji and ha and the prominent chikei completing the judgment. At the flamboyant top end the confusion runs instead toward Ichimonji, and there a koshi-biraki opening in the midare and nie clotting even inside the ha settle the attribution; that koshi-open manner marks the small sub-group of the Tenkyuwari look, an anchor for mumei blades of the same air. The shirajimi too is a keyed feature rather than a constant: the texts note that 'this phenomenon is frequent in the works with a flamboyant midare temper and is little seen in those of a suguha-toned make'[[c:4]]. The lineage is kept clean at the root: the Naomune line stands apart from the Osafune mainline, and Nakahara Kunimune, whose dated tachi run from Kagen to Engyo in a quiet suguha base, is regarded as a pupil of the first generation.

For the connoisseur, Kunimune is Sai-jo saku in Fujishiro's grading, with three National Treasures, ten Important Cultural Properties and eight Tokubetsu Juyo among ninety-seven designated works on record. The National Treasure tachi of Terukuni Jinja in Kagoshima stands at the head of his signed work; the Nikko Toshogu tachi is the National Treasure of his rarer nie-based hand. The named blade Tenkyuwari carries one of the great sword histories: it was the sword Uesugi Kenshin wore when he broke the camp of Takeda Shingen's brother Tenkyu Nobushige at Kawanakajima, was given by Kenshin to Satake Yoshishige, and was held thereafter in the Satake house, lords of Kubota in Dewa, with an itomaki tachi koshirae of Kansei date. The Uesugi, Satake and Shimazu, the Kishu and Owari Tokugawa, the Ii and Abe houses and the Imperial Household appear among his recorded owners, and one tachi reached the Boston Museum of Fine Arts. About sixty-three of his blades fall in the Tokubetsu Juyo and Juyo tiers, which makes a designated Kunimune among the more attainable of the great Kamakura names; the National Treasures and Important Cultural Properties are heritage held in shrines and museums and do not trade, while a Tokubetsu Juyo or Juyo example, most of them held rather than offered, comes to a private collector only with patience, and is a major acquisition when it does, the one realistic way to own the Bizen master whose journey east stands behind the rise of Soshu.