The Kaifu group of Awa Province traces its founding to Kaifu Taro Ujiyoshi, placed by the Koto Meizukushi around the Koryaku era (1379-1381). No works by this earliest Ujiyoshi survive, however, and it is from the latter half of the Muromachi period that the activity of the Kaifu smiths becomes conspicuous. The name Ujiyoshi was carried forward across multiple generations, with extant signed blades ranging from the mid-Muromachi period through to a rare shinto-period example -- a wakizashi in the Imperial Collection (Gyobutsu) by a Kyoho-era Ujiyoshi whose workmanship, the setsumei observe, is "almost exactly like what one sees in late koto work," suggesting his ancestors' style was transmitted unchanged.

The setsumei characterize Kaifu workmanship by a tightly forged ko-itame accompanied by dense ji-nie and chikei; a broad suguha-based hamon into which midare, gunome, and shallow notare are mixed; and a deep nioi with adhering ko-nie. The overall impression, one examiner notes, "at a glance calls to mind Go Yoshihiro" -- a deeply tempered, powerful style distinctive among provincial smiths. The katana known as "Iwakiri Kaifu," recorded in the Kyoho Meibutsu-cho, exemplifies this character. Formerly in the possession of the Miyoshi family of Awa, it is transmitted that the warlord Miyoshi Nagayoshi achieved martial exploits with this blade before it passed into the hands of the Kuroda family of Fukuoka.

The Kaifu group occupies a distinctive position among late koto provincial schools. Their ability to produce blades of a character reminiscent of the great Soshu tradition, combined with the historical resonance of the Iwakiri Kaifu and its Meibutsu-cho pedigree, elevates Ujiyoshi beyond the level of a regional craftsman to a name of recognized importance in the koto canon.