Although western learning had been banned by the Edo bakufu (Japanese feudal government headed by a shogun), which was concerning about the effect of Christianity, at the earliest stage of the commerce between the West, the ban was lifted as a part of the reformation in the period of Yoshimune TOKUGAWA, the 8th seii taishogun (literally, great general who subdues the barbarians) and the history of Rangaku in Japan was started.
西洋との交流が始まった最初期は西洋のキリスト教による影響を鑑みて江戸幕府は蘭学の禁止を打ち出していたが、八代征夷大将軍徳川吉宗公の代に改革の一部として解禁され日本の蘭学史が幕を開けた。