thumb|Taiwan map detail, from Qing Dynasty Map during Xinhai Revolution
Taiwan (also known as Formosa) is an island located off the coast of Fujian in mainland China. The Chinese and Taiwanese people have a long history together, with the first Han Chinese settlers arriving in Taiwan in the seventeenth century. The Japanese empire acquired Taiwan (also known as Formosa) following its cession from Qing dynasty China in the Treaty of Shimonoseki (1895) at the conclusion of the First Sino-Japanese War. This period of Japanese rule of Taiwan lasted until the surrender of Japan.
There is a long history of opium use in Taiwan dating back to the arrival of the Han Chinese settlers in the 18th Century. Opium has been used throughout history recreationally and as medicine, with historians predicting that opium was likely introduced throughout East Asia in the sixth century A.D. along the Silk Road trade route. While opium presented the opportunity for a lucrative trading market to many countries, the devastating impact of the addictive substance caused havoc across East Asia as well as throughout the US and Europe. These fears may have stemmed from their observation of its effects on the Chinese population as well as aggression from western powers to force its export.
These fears were exacerbated by American diplomats such as Townsend Harris that described opium as "the one great enemy of China" and that it "injures like the most deadly poison". The Prime Minister at the negotiation of the Treaty of Shimonoseki, Itō Hirobumi expressed that "There have been people living in Taiwan long before the arrival of opium,” The Qing dynasty was underprepared for the war and was overwhelmed by the power and force of the Japanese fleet. which conceded Taiwan to Japanese rule in perpetuity. During the first three years of Japan's colonial rule, the Japanese military governed the island. However, in 1898 Tōkyō began appointing Japanese Governors to oversee Taiwan. Their initial policies focused on growing the agricultural industry by working to improve production outputs and farming techniques. Although Formosa was not technically assimilated with Japanese culture, the local Taiwanese populations were forced to speak Japanese instead of their native language resulting in the loss of local culture. The practise of smoking opium was seen as primitive and dangerous by the Japanese hick as a threat to their ideology and their perception in the global world. The policy meant Taiwanese nationals who already addicted to opium could continue to smoke under government regulation. However, by the 1920s there were as many unregistered opium users as registered opium users. The imbalance between the number of registered and unregistered opium smokers demonstrated that the policy was ineffective at keeping nonusers from taking up smoking. The government was in the process of making the opium trade a monopoly for their individual gain, whilst simultaneously developing policies which permitted users to continue smoking and prohibited people from starting to smoke.