During his presidency, Lee supported the Taiwanese localization movement. The Taiwanization movement has its roots in Japanese rule founded during the Japanese era and sought to put emphasis on vernacular Taiwanese culture in Taiwan as the center of people's lives as opposed to Nationalist China. During the Chiang era, China was promoted as the center of an ideology that would build a Chinese national outlook in a people who had once considered themselves Japanese subjects. Taiwan was often relegated to a backwater province of China in the KMT-supported history books. People were discouraged from studying local Taiwanese customs, which were to be replaced by mainstream Chinese customs. Lee sought to turn Taiwan into a center rather than an appendage. In 1997, he presided over the adoption of the Taiwan-centric history textbook "Knowing Taiwan".