During more than three decades of his educational career in China, William B. Pettus developed in Beijing (then Peking) an extraordinarily successful Chinese language and cultural college for Americans and other non-Chinese speakers.  Pettus became the president of the institution in 1916 and retired in 1945.  After that he continued to work as the president of the California College in China Foundation, which promoted and assisted in China studies.  The College had trained thousands of Americans in Chinese language and culture and its graduates served in a wide range of American government, diplomacy, military, academic organizations, etc.

The Japanese occupation of Beijing in 1937 changed the political, educational, cultural, and intellectual environment of the college and Pettus began returning to the United States.  In 1940 and 1941 before Pearl Harbor, a valuable portion of the largest library of the college and teaching materials was shipped to the United States for safekeeping.  Some of the shipment was lost and never reached the American shores.

After Pettus established a refuge institution of the California College in China at the University of California, Berkeley, these books and materials were used to serve the Chinese language instruction.  When WWII ended, the college completed its mission of preparing army and navy officers.   In 1946, this collection of some 5000 volumes and other materials was transferred to Claremont Graduate University, then called Claremont Graduate School.  This served the Claremont Colleges and the Society for Oriental Studies in the interest of Asian studies.  The ancient Chinese books were kept in a separate location and the rest were put into general circulation.

When the Honnold Library was built, the Claremont Graduate University's library which was previously located in Harper Hall was moved into the new building and the separately-kept books were housed in a locked back room in the Asian Studies section of the library.  Now, this collection is elegantly and securely held in a well-appointed room, together with other Chinese artifacts on the third floor in Asian Studies of Honnold Library.