The Uda school traces its origins to Ko-Nyūdō Kunimitsu, a monk-smith who migrated from Uda District in Yamato Province to Province during the late period, traditionally around the Bunpō era (1317–1319). The school flourished through successive generations during the period, with smiths such as Kunifusa, Kunimune, and Kunitsugu carrying the tradition forward. The names were inherited across generations, and the lineage continued to prosper through the period and even into the era. Works produced from the late through the period that do not descend later than this era are collectively referred to as "," representing the school's formative period before later developments.
Because the school originated in Yamato, works naturally display a strong Yamato temperament in their fundamental character. The forging typically shows mixed with , often with flowing grain () and occasional tendencies, particularly on the rear face. The frequently exhibits (standing grain) and tends toward a darkened, somewhat blackish tone in the steel, with areas that can appear kasudatsu (rough, chaffy texture)—features that reveal a distinctive northern-province character. Thick adheres densely, and bold enter well. The is characteristically , typically presenting or tempered lines, sometimes with shallow and mixed or . The is abundant and well-applied, with deep ; the edge frequently shows (fraying), uchi-noke, and vigorous activities including , , and , occasionally suggesting (double-layered temper). The characteristically tends toward (subdued quality) or takes on an (moist, soft) feeling. The typically shows with a rounded or turnback, often somewhat deep.
While the Yamato temperament forms the foundation of Uda workmanship, certain examples also reveal strong influences from the tradition, thought to emulate earlier masters such as Norishige and the smith called Gō. This dual character—combining Yamato restraint with vigor—creates works that at first glance can recall high-ranking masters through their powerful , active and , and dynamic construction. However, the distinguishing features remain: the dark-toned with its characteristic northern grain texture, the subdued , and the frequent fraying of the . Despite their quiet, restrained appearance, works possess an exceptionally deep, lingering quality—a calm yet vigorous manner filled with subdued elegance ( yet with gami). Both and demonstrate sound craftsmanship, and the school's works are valued for their archaic dignity and the distinctive way they bridge Yamato tradition with innovation.