After three years under Myôju, Tadayoshi returned to Hizen and with funds made available through the Nabeshima daimyo he set up his forge and took on sixteen relatives and 60 or so local workers under employment in sword manufacture.Over the years he would sign his swords in various different ways, beginning with a simple five character signature (gojimei) Hizen (no) Kuni Tadayoshi (肥前国忠吉).For the last part under the Tadahiro name this rises to 4.75 Juyo per year.During the end of his life he dealt with a fair amount of sickness too, and I theorize that the swords he made and signed himself as Tadahiro were likely above the commercial caliber of swords previously made and that were continuing to be made by the large number of swordsmiths working in his forge.His father was a swordsmith of average average ability who signed under the name Michihiro. Instead he took up sword crafting in the village of Nagase-Mura.Roger Robertshaw's excellent reference books The School of Hizen Tadayoshi states that his teacher was likely Iyo no jo Munetsugu.The house style is based on the work of Yamashiro Rai, and swiftly gained and maintained a reputation for high quality swords, both beautiful and practical with excellent cutting ability.Tadayoshi was born in 1572 and began learning sword-craft at the end of the koto period. His father and grandfather (Morihiro) were both in the service of the Nabeshima daimyo and at the time of his father's death, Tadayoshi was too young for service.
Umetada Myôju granted Tadayoshi the tada character (忠) which has been faithfully handed down the main Hizen line ever since.The combination of these two I think increases the number of masterpieces that are directly associated with his personal work.During the last period of his life Tadayoshi took orders from the Nabeshima daimyo to make a special form of blade to be used as gifts.Myôju was able to produce high quality copies of the work of Shizu and Sadamune, and early Tadayoshi work of this period follows his teacher in exploring these forms.Throughout the history of the Hizen school a midareba which is based on this work appears as part of the repertoire its smiths.
By my count there are 96 Juyo blades by Tadayoshi which is an extremely high number for a Shinto smith.