Sukezane (助真) was a swordsmith who represents the peak flourishing of the Fukuoka school of Province in the mid- period. Together with Yoshifusa and Norifusa, he stands as one of the three foremost masters who signed with individual names during the school's zenith. Tradition holds that he was a son of Sukefusa, and that he later relocated to in at the order of the shogunate, together with Saburo Kunimune and Kunitsuna of Yamashiro. His name appears in the smith genealogies of the Kanchi-inbon Meizukushi, and from old times there has been the appellation " ." The celebrated "Nikko Sukezane," a National Treasure and favored sword of Tokugawa Ieyasu, stands as the archetypal example of his art. Two distinct signature manners are recognized: one cut above the toward the with a finer, sharper chisel, and another cut below the with a thicker chisel in a rounded calligraphic style, each associated with differing workmanship tendencies.
All three principal masters produced splendid , yet the consistently distinguishes Sukezane by observing that his and are "a step stronger than those of the other smiths" and that "even amid its brilliance it overflows with a sense of power." His is characteristically mixed with , with thickly adhering and fine , producing conspicuous . The centers on large-cluster obusa-, frequently incorporating , -, and -, yielding a flamboyant irregularity with pronounced rises and falls. In particular, adheres well within the , and and run vigorously — features that "reveal a manner distinctive to this smith." The possesses a characteristic, slightly somber "susudoshi-like" quality. A second workmanship type shows gentler, sometimes slender with comparatively small-patterned or -based tempering mixed with , , and , where thick extends into the interior of the . These works display "a manner reminiscent of " and are valued as "documentary material for understanding Sukezane's range." A - coloration is also noted, with one observing that it "convincingly explains why the term came into use."
Across designation records at the highest levels, Sukezane's works are consistently described as possessing "the most bold and exuberant" character, "full of spirit," with both and remaining — sound and well-preserved. The regards his oeuvre as manifesting "the highlights of Fukuoka to the full," while his -enriched, -laden style sets him apart from the -dominant mainstream of the school. That signed examples remain comparatively few lends additional documentary significance to each surviving . His blades carry illustrious provenance through the Kishu Tokugawa, Okudaira, Ikeda, Hachisuka, and Mori families, with appraisals attesting to valuations of thirty-five gold and above. Within the lineage, Sukezane occupies the singular position of the smith whose powerful individuality transcended school convention, bridging the refined - aesthetic with the emerging -dominant strength that would come to define the tradition.