Canton System

The Canton System (1757–1842) served as a means for China to control trade with the west within its own country by focusing all trade on the southern port of Canton (now Guangzhou). Known in Chinese as the Yī kǒu tōng shāng (一口通商, "Single port commerce system") the policy arose in 1757 as a response to a perceived political and commercial threat from abroad on the part of successive Chinese emperors.
From the late seventeenth century onwards, Chinese merchants known as Hongs (háng, 行 ) managed all trade in the port. Operating from the Thirteen Factories located on the banks of the Pearl River outside Canton, in 1760, by order of the Qing Qianlong Emperor, they became officially sanctioned as a monopoly known as the Cohong. Thereafter Chinese merchants dealing with foreign trade (known as yángháng (洋行, literally "ocean traders") acted through the Cohong under the supervision of the Guangdong Customs Supervisor (Yuèhǎi guānbù jiàn dù, 粵海關部監督), informally known as the "Hoppo", and the Governor-general of Guangzhou and Guangxi.

At the start of his reign, the Kangxi Emperor (r. 1661–1722) faced a number of challenges, not the least of which was to integrate his relatively new dynasty with the Chinese Han majority. The Manchu Qing had only come to power in 1644, replacing the Ming dynasty. Support for the previous rulers remained strong, particularly in the south of the country. Kangxi twice banned all maritime trade for strategic reasons, to prevent any possible waterborne coup attempt. Several rebellions took place, including one led by Ming loyalist Koxinga and separately the Rebellion of the Three Feudatories, which led to the capture of Taiwan in 1683. Once the rebellions had been quelled, in 1684 Kangxi issued an edict:

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