Among his early scholarly writings were
The Democratic Movement in Asia (1918) and
A Better World (1920). In 1922, he published
Americans in Eastern Asia, a study of American policy in the Far East, which was well received and was long held as an important work in the field. Dennett published "President Roosevelt's Secret Pact with Japan" in 1924, the subject of which came to be known as the
Taft–Katsura Agreement. The paper put forth the thesis that formerly-isolationist Japan and the US began to carve up their
spheres of influence, which would later become world empires, with the agreement, which was therefore of first-class importance historically. Later historians questioned that interpretation. Dennett was awarded a Ph.D. in history from
Johns Hopkins University in 1925 based on this research on
Theodore Roosevelt and the
Russo-Japanese War. He taught American history at
Johns Hopkins University (1923–24) and at
Columbia University (1927–28), and
international relations at
Princeton University (1931–34). Most significantly, Dennett served as president of
Williams College (1934–37), resigning after a disagreement with the college's board of trustees. The trustees planned to purchase the Greylock Hotel, which later became a dorm, but at the time Dennett felt the hotel had no useful purpose for the college. Dennett was also one of the future college presidents to speak out against Nazi Germany during this period, ending academic exchange programs with Nazi Germany in 1936. He received the 1934
Pulitzer Prize for Biography or Autobiography for his book,
John Hay: From Poetry to Politics (1933). ==Death==