德川齊昭
Around the end of the eighteenth century, Mitogaku came to address contemporary social and political issues, beginning the era of Later Mitogaku. The ninth Mito clan leader, Tokugawa Nariaki (1800–1860), greatly expanded Mitogaku by establishing the Kōdōkan as the clan school. In addition to Confucianist and kokugaku thought, the school also absorbed knowledge from medicine, astronomy and other natural sciences. The Later Mitogaku era lasted until the Bakumatsu period. The school exerted a major influence on the sonnō jōi movement and became one of the driving forces behind the Meiji Restoration. However, it failed to gain the protection of the new government and the "Kōdōkan" was disbanded and its library largely taken over by the state.