Ogasawara clan
Dr. Tanaka himself found out that the locations "Haratono-hama" and "Harayadori" are fictitious. To make the anecdote sound credible, the author designated the beaches as personal acreages of a Daimyō named Ogasawara Nagashige. This daimyō actually lived during the Edo period, but his acreages were placed at heartland and it seems sure that Ogasawara never had any contact with the fishermen of the Pacific coast. The Ogasawara clan served the famous Tokugawa clan, who held power over the most north-eastern part of Japan until 1868 and their main acreages were placed in the Hitashi province, geographically very close to the eastern beaches.