Saemon-no-jo Naganori was a late-period smith of the Fukuoka lineage, which flourished in the Fukuoka area of Province and traces its origin to Norimune, who served as one of the (swordsmiths in attendance) to Retired Emperor Gotoba. Among extant works bearing inscriptions that explicitly include "Fukuoka-ju" ("resident of Fukuoka"), the earliest begin with Naganori; indeed, apart from this smith, signed works stating "Fukuoka" are scarcely encountered from any other maker within the lineage. He consistently cut a long signature reading " no Fukuoka-ju Saemon-no-jo Naganori ," and dated works survive from the Einin (1293--1299), Shodan (1299--1302), and Kagen (1303--1306) eras, placing him later in period than such celebrated predecessors as Yoshifusa and Sukezane. One theory holds that Naganori was the individual as Naganori, whose second generation relocated to Yoshii, giving rise to the branch. A separate genealogy identifies a smith named Naganori as the founder of the Doei lineage of Izumo Province. He has also come to be colloquially called "Ko-ryu Naganori," though the reason for this appellation is not clearly understood.
Perhaps reflecting the influence of the times, Naganori's manner differs markedly from the flamboyant - in brilliant profusion for which the Fukuoka school is famed. His workmanship instead shows a calm and gentle character: principally slender in which he tempers a -based mixed with and , the small running in continuity from base to tip. and enter frequently, and the characteristically shows a (tightened) tendency. His work is chiefly , accompanied by , with fine and appearing through the temper. The forging presents a dense , at times mixed with and tending toward slightly standing grain, with fine adhering and entering. A particularly striking identifying feature is the appearance of vivid , which stands out with exceptional clarity and, in some examples, transitions to or in the upper portion of the blade. Among his , one encounters examples in a narrow with a slight tendency. His is typically slender with high , pronounced , and or compact , presenting a stately and dignified bearing.
The repeatedly distinguishes Naganori as a smith who "differs in character from the flamboyant temper patterns typical of the school" and whose work displays instead "a calm workmanship" of subdued refinement. His style is described as sharing "common ground with smiths such as Kagemitsu and Chikakage," though as a distinguishing feature he tends to display somewhat more prominently than Kagemitsu and related makers. The workmanship associated with , an extension of his legacy, is especially noteworthy for in running in connected sequences, with examples of "particularly superior quality" that "at a glance, call to mind works by Kagemitsu." His signed and dated blades are praised not only for their technical merit but as constituting "valuable reference material" and documentation "of high documentary value" for the school's history. Individual works are described as (sound and well-preserved), and those retaining tangs in full form are recognized as especially imposing. Naganori occupies a singular position within the Fukuoka tradition: the only smith to claim the Fukuoka provenance in his signature, and a maker whose restrained, -dominant aesthetic marks the school's late evolution from the exuberant of its mid- zenith toward the refined sensibility of the closing period.