The Bansha no goku refers to the 1839 suppression of scholars of Western Studies (rangaku

Rangaku

Rangaku is a body of knowledge developed by Japan through its contacts with the Dutch enclave of Dejima, which allowed Japan to keep abreast of Western technology and medicine in the period when the country was closed to foreigners, 1641–1853, because of the Tokugawa shogunate’s policy of national...

) by the Edo Shogunate government of Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

.

The incident was provoked by criticism of the isolationist sakoku

Sakoku

was the foreign relations policy of Japan under which no foreigner could enter nor could any Japanese leave the country on penalty of death. The policy was enacted by the Tokugawa shogunate under Tokugawa Iemitsu through a number of edicts and policies from 1633–39 and remained in effect until...

 policy due to actions such as the Morrison Incident

Morrison Incident

The of 1837 occurred when the American merchant ship, Morrison headed by Charles W. King, was driven away from "sakoku" Japan by cannon fire...

 when an unarmed American merchant ship was fired upon under the Edict to Repel Foreign Ships.

Among those who suffered from this action were Watanabe Kazan

Watanabe Kazan

was a Japanese painter, scholar and statesman member of the samurai class.- Early life :He was born Watanabe Sadayasu in Edo to a poor samurai family, and his artistic talent was developed from an early age. His family served the lord of the Tahara Domain, located in present day Aichi prefecture....

, Takano Chōei

Takano Choei

was a prominent scholar of Rangaku of the late Edo period.Chōei was born as Gotō Kyōsai, the third son of Gotō Sōsuke who was a middle ranking samurai in Mizusawa Domain of Mutsu Province which is in present-day Iwate Prefecture...

 and Koseki Sanei.