Shinkai (1630-1682), son of Kunisada I, was born in Osaka and worked as a retainer to the Ito family, daimyo of Obi in Hyuga, where he made swords which received high praise for their first-quality koto style and workmanship. In 1652 he received the honorary title of Izumi (no) Kami (Lord of Izumi), as had his father, and for the next twenty years used several signatures (Izumi (no) Kami Fujiwara Kunisada, Inoue Izumi (no) Kami Kunisada, Sesshu Osaka (no) ju Inoue Izumi (no) Kami Fujiwara Kunisada, oite Osaka Izumi (no) Kami Kunisada, etc.). On July 12th, 1672, he changed his name to Inoue Shinkai, which he used until his death ten years later. In 1669 he developed a style of his own based on the works of Go Yoshihiro. He made broad, Soshu-inspired swords of shallow curvature, ko-itame forging and a wide tempering pattern in dense nie.
Blades bearing the Inoue Izumi (no) Kami Kunisada signature appear to date from Manji 4 (1661) to Kanbun 12 (1672), and those blades on which the kiku bears a single punch in the center (rather than a crosshatch) appear to date from Kanbun 4 (1664).
This blade displays a particularly strong Soshu influence, especially when compared to the katana dated Enpo 4 (1667) in Part I of the Compton Collection (lot 356). The controlled, fine-grained pear skin forging pattern serves as an excellent foil to the rather unsubtle display of nie, which takes the form of 'swept sands', and and gives the illusion of sudare-ba as well as straying over into the ji.
The artist who worked on the saya would appear was an inro artist. He was almost certainly associated in some way with the Kajikawa school, but is unrecorded. One other piece bearing a Gyokuryusai signature appeared as item 157 in the Arthur Kay auction, Paris, 1913.