The blockade by the Japanese occupying army in China of the British and French settlements in the North China Treaty Port of Tientsin in June 1939 originated as a minor administrative dispute and escalated into a major international issue. This book examines why the incident was not resolved locally, the reasons for escalation and why a solution continued to be elusive. In charting the development of the crisis, emphasis is put on the interaction of a broad range of local, regional, national and international factors. These include the hostility engendered by Japan's occupation of China; the role of Tientsin in Japan's narcotics trade; a growing tendency within Japan to utilize any opportunity to blame western powers and particularly Britain for Japan's Chinese occupation woes; and British and French efforts to take advantage of the incident to pressure the United States to shore up their waning imperial interests in Asia by adopting a more overtly anti-Japanese stance. A major theme of the study is theextent to which the course of this incident was affected by both Japan and Britain's insensitivity towards China and their inability to contain a determined and creative popular Chinese movement to reclaim a greater control over the course of their national destiny.