Prior research has shown great interest in the process and mechanism of innovation diffusion. This study demonstrates the influence of network position on innovation diffusion by analyzing “hanko," which were schools for clan retainers in the Edo period in Japan. We create an external knowledge network of hanko that was formed by ties when hanko taught the same subjects. We employ statistical analysis using network position indexes. The results contribute not only to revealing the adaptation process of new studies but to revealing the process and mechanism of knowledge transfer and diffusion.