The line begins with a Mino man. The setsumei record that Sagami no Kami Masatsune (政常) was born at Nōdo in Mino Province, where he first signed Kanetsune (兼常) and is variously said to have been the son or a disciple of Kanetsune of Seki. In Eiroku 10 (1567) he established an independent branch line and moved to Komaki village, likely changing his name to Masatsune about that time; in the fifth month of Tenshō 19 (1591) he received the court title Sagami no Kami, and in Keichō 5 (1600) he followed Matsudaira Tadayoshi to Kiyosu in Owari, where he became a retained smith (kakae-kō) of the Owari Tokugawa house. Several records place him at Kiyosu alongside Hōki no Kami Nobutaka and Hida no Kami Ujifusa, the three later counted as the Owari Sansaku (Three Smiths of Owari). After taking the tonsure and retiring in Keichō 12 (1607), he passed the name to his son; when that second generation died suddenly two years later he resumed forging under the nyūdō signature Masatsune Nyūdō, and is said to have died in Genna 5 (1619) at the age of eighty-four. A separate second generation, Mino no Kami Fujiwara Masatsune, is recorded as the son of Daidō of Gifu, adopted into the line, who carried on its spear and naginata work. A Mino foundation worked toward suguha defines the shared hand. The forging is itame mixed with mokume, frequently flowing into masame toward the mune and shinogi-ji, with the grain standing somewhat (hada-dachi), abundant ji-nie, and chikei; a mizukage-like feature rising from the machi is noted on several tantō and wakizashi.
The temper that the setsumei call his specialty is a chū- to broad suguha in ko-nie-deki, the habuchi worked with hotsure, nijūba, kuichigai-ba, and uchi-noke, with ko-gunome and ko-ashi mixed in, fine kinsuji and sunagashi running through, and a bright nioiguchi. Beside this restrained mode runs a bolder midareba of gunome and ko-notare with togariba, sometimes hakogakari or saka-gakari, where the nie grows coarse and clustered and the nioiguchi turns shizumi (subdued); the Owari-Seki "wet" nure quality appears in the wider blades. The bōshi tends to straight with ko-maru and hakikake in the suguha works, midare-komi with a rounded or long return in the midareba works. Carving is plain but crisp: suken, bonji, gomabashi, koshi-hi with soe-hi, and the rarely seen shin no Kurikara in openwork. Among extant works, the setsumei agree, hira-zukuri wakizashi and tantō are the most numerous and of high skill, yari and naginata are comparatively common with the spears often hira-sankaku sasaho form, while katana and shinogi-zukuri wakizashi are extremely few. For kantei this rarity gives weight to the long swords: the 67th Jūyō Kanetsune-signed katana, dated by its sakizori and large kissaki to about Eiroku, anchors the smith's early phase, and the 31st Jūyō Masatsune Nyūdō katana shows the flowing masame, shallow notare, and shizumi nioiguchi read as his own. Named pieces include the Sagami no Kami Masatsune Nyūdō wakizashi held by the Imperial Household Agency and the katana once with Tokugawa Iesato and the Reimeikai Foundation; one wakizashi survives in akikusa-mon koshirae with fittings by Mogarashi Sōten of Hikone. The setsumei note that in his bolder work Masatsune looked to the Sagami masters Sadamune and Nobukuni while keeping the togari and Sanbon-sugi traces of his Mino root, placing his line as the Owari channel through which the Mino-den passed into shintō. Learn more →