The first-generation Tanba no Kami Yoshimichi was the third son of Kanemichi of , with elder brothers Iga no Kami Kinmichi and Kinmichi, and a younger brother no Kami Masatoshi. During the Eiroku era, he relocated with his father and brothers from to Kyoto, where they greatly enhanced the reputation of the group, collectively celebrated as the -ikka. Active from the Keichō through 'ei eras, Yoshimichi established a lineage of extraordinary longevity: his descendants and pupils continued vigorous activity across multiple generations in both Kyoto and Osaka. The Osaka branch was founded by his second son, who moved there during the 'ei era; the distinction between Kyō-Tanba and Ōsaka-Tanba is famously marked by the rendering of the character "mori" in the signature. A subsequent generation, the nidai Yamato no Kami Yoshimichi, worked in Osaka and Himeji around the Shōō and Manji eras, further extending the family's reach.
Yoshimichi's defining technical achievement is , the "bamboo-blind" he himself devised. In his characteristic mode, a long at the base gives way to broad in mixed with ; at the , vigorous and intermingle while persistent creates a distinctive striped appearance. The adheres thickly, with patches of coarser producing slight unevenness, and enter frequently. The Ben'i observes that in the first generation's work "within the patterned arrangement of the there lies the spirit of ." This captures the essential quality: unlike later generations, whose became "technical and exaggerated," the 's and break forth "like gyōsō script" in semi-cursive disorder. The fact that it has not yet become a fully perfected is itself the principal point of interest, conveying both power and depth of flavor. His is typically mixed with , occasionally tending toward or , with thick and fine . The often rises with a tendency and vigorous -- the " ." His in favors bold with wide , thick , and proportions characteristic of Keichō ; his display standard width with clear taper and . Though rooted in the tradition, he also produced rare works in and large , demonstrating versatility. His distinctive five-character signature, "cut with fine chiselwork yet in large, bold strokes" and placed toward the , includes the celebrated character "Tan" whose form earned him the sobriquet Hokake Tanba.
The consistently praises the 's works as possessing "force and depth of taste" that distinguishes them from later generations' more formulaic output. Works in which the is "skillfully brought together and well concluded" are singled out as typical of his finest manner, while pieces with quieter, more refined irregularities are described as works in which "the is tight and presents an excellent-quality texture." Whether in the overtly dramatic or the restrained , the Yoshimichi's oeuvre is recognized as occupying a singular position within the tradition -- the originator of a signature style whose incomplete, vigorous character remains more compelling than its later perfected descendants.