At first, interpreters began to study Rangaku, and Hakuseki ARAI demonstrated the enlightened understanding of overseas circumstances in his book "Seiyo kibun" (Western Accounts), and then, Yoshimune TOKUGAWA relaxed the import ban on Chinese translations of Dutch documents, and told Konmei AOKI and Genjo NORO to study Dutch and promoted practical learning, which eventually allowed Rangaku to thrive.
通詞によって学ばれ始め、新井白石が『西洋紀聞』で開明的な海外理解を示し、徳川吉宗が漢訳蘭書の輸入禁止を緩和し、青木昆陽、野呂元丈に蘭語学習を命じ、実学を奨励したのちに盛んになった。