At the invitation of his classmate, Fang Chao-ying, who was collaborating with Arthur W. Hummel, Sr. on the monumental Eminent Chinese of the Ch'ing Period (Washington, D.C.: Government Printing Office, 1943), Teng turned his attention to biography and eventually contributed thirty-three articles, most of them dealing with the Taiping Rebellion of the mid-19th century.
He and Fairbank teamed on a series of articles in the Harvard Journal of Asiatic Studies which exploited the newly published archives to explain the structure of the Qing dynasty's initial interaction with the west.
[1] In 1941, Teng joined the University of Chicago as Assistant Professor of Chinese History and Literature and as Acting Director of the Far East Library.
To these he added items in Howard Boorman, et al. eds, Biographical Dictionary of Republican China, the emergence of Japanese studies on Japan and the Far East, and Chinese secret societies in the Twentieth Century.
In their "Indiana University Faculty Memorial Resolution", after Teng's death, two of his colleagues commented that "More than an accomplished historian, he was a consummate bibliographer whose range and depth of knowledge of Chinese writers and writings were extraordinary."