Although in the 1860s the European silk industry had far surpassed Japan technologically, the silkworm population in Europe was almost destroyed by two diseases: pébrine, an affliction caused by a fungal parasite that makes silkworm larva unable to spin cocoons, and bouffée flacherie, a non-infectious disease caused by exposure to extreme heat that causes the larvae to turn flaccid and die. Prices for healthy silkworm eggs skyrocketed in Europe, and both silk and eggs were sold in great volume at the newly opened silk markets of Yokohama.
Around the same time, farmers from the village of Shimamura (now part of Isesaki, in Gunma Prefecture) formed a sericulture collective, working together to raise silkworms and produce high-quality silk. After the Meiji period, they reorganized into a company called Shimamura Kangyo. This company sent a group led by a man named Tajima Yahei (1822–1898) to sell silkworm eggs directly to Italian silkworm farmers. As one of the founding members of Shimamura Kangyo, Yahei is remembered as one of the leaders of the silk revolution.
Yahei also designed a building for raising silkworms. The second floor of the long building had a raised section of roof with windows that could be opened to admit outside air. Using this design, farmers were able to control airflow and maintain an ideal temperature around the silkworms. The fresh air protected the silkworms from disease, improved their yields, and increased the reliability of the silkworm crop. Yahei’s design quickly spread throughout the Shimamura community and other parts of Japan. In recognition of the massive impact that his contributions had on Japanese sericulture, his house is included as part of the World Heritage Site.