 During the Sengoku period, it was frequently a battlefield, coming under the control of warlord Sassa Narimasa, who built a castle town around Toyama Castle and channeled rivers to bringing about a flourishing agricultural industry.The area subsequently became part of Kaga Domain under the Maeda clan during the Edo period, during which time a positive industrial promotion policy was implemented on the production of Chinese medicine and "washi" (Japanese paper).Also, thanks to the improvement of "kitamaebune" sea transportation routes, these industries thrived and Toyama became known nationwide as the province of medicine.