Maritime Trade in Imperial China: Sea Routes, Ports, and the Ming Sea Ban

The maritime trade of imperial China was, for most of the imperial period, the larger and more dynamic half of Chinese foreign commerce. While the overland Silk Road carried silk, spices, and ideas across the Eurasian heartland, the maritime routes through the South China Sea, the Indian Ocean, and (eventually) the Pacific carried the bulk of Chinese exports and brought in the silver, spices, and exotic luxuries the empire consumed. By the late imperial period, a change in the global silver supply could bring down a dynasty, and a change in Chinese state policy toward maritime commerce could reshape the global economy. The broader context of the Silk Road and Chinese foreign trade sets out the overland routes in comparison, and the history of what was traded on the Silk Road details the goods that moved by sea.

The Tang and Song Foundations

Chinese ships had plied the South China Sea since at least the Han. The Tang Dynasty was the moment when the maritime trade first became a major part of the Chinese economy, and the Song Dynasty was the moment when Chinese shipping and Chinese merchants became dominant in the South China Sea and the Indian Ocean. The Tang ports of Guangzhou, Yangzhou, and Fuzhou were major centers of foreign commerce, and the An Lushan Rebellion of 755–763 disrupted the overland routes and increased the relative importance of the maritime trade. Tang Chinese ships reached as far as the Persian Gulf.

The Song Dynasty was the first great age of Chinese maritime commerce. The Northern Song lost the northern overland routes and was forced to depend on the sea for foreign trade; the Southern Song, with its capital at Hangzhou near the coast, was even more maritime in orientation. The Song built a sophisticated merchant marine, with multi-masted junks equipped with watertight bulkheads, the magnetic compass, the sternpost rudder, and complex sail rigs. The Song customs office at Quanzhou was one of the most productive revenue offices in the empire, and Song copper coins have been found on archaeological sites as far away as East Africa. The deeper treatment of the broader economic transformation is in the history of the imperial Chinese economy, and the history of imperial China places the Song in its dynastic context.

The Great Ports: Quanzhou and Guangzhou

The maritime trade was anchored in a small number of great ports. Quanzhou in Fujian, Guangzhou in Guangdong, Hangzhou in Zhejiang, and Yangzhou on the Yangzi were the most important.

Quanzhou was one of the greatest ports in the world in the Song and Yuan periods. The city had a population of perhaps two million in its hinterland, and its port was crowded with ships from every part of maritime Asia. Quanzhou had a large foreign merchant community, including Arabs, Persians, Indians, and Southeast Asians; it had Nestorian Christian, Manichaean, Islamic, and Hindu temples; and it was governed by a Song and then Yuan customs office. Giovanni da Montecorvino and Ibn Battuta both described Quanzhou as one of the great ports of the world. Its golden age ended with the early Ming sea ban.

Guangzhou had a long history as a foreign-trade center from the Han onward, and it was a major port in every major dynasty. In the late Ming and Qing, after the restriction of foreign trade to the single port under the canton system, Guangzhou became the principal gateway for European commerce, and it was through Guangzhou that the British tea trade, the opium trade, and the silver-and-tea circuit of the late Qing operated. The breakdown of the Guangzhou-based trade in the nineteenth century was a major step on the road to the fall of imperial China.

The Ming Maritime Expeditions and the Sea Ban

The early Ming presided over both the high-water mark of Chinese maritime power and the most severe restrictions on Chinese maritime commerce. The Yongle emperor (r. 1402–1424) sent the eunuch admiral Zheng He, a Muslim from Yunnan, on seven great voyages between 1405 and 1433. The treasure fleets were enormous: the first expedition included 317 ships and perhaps 28,000 crew, and the largest ships were more than 120 meters long. The expeditions reached as far as the Swahili coast, the Red Sea, and the Persian Gulf, and they projected the Yongle emperor’s prestige across maritime Asia.

The Ming abruptly ended the maritime expeditions in 1433. The succeeding emperors were anxious about the cost, suspicious of the merchants who had profited from the trade, and fearful of social disruption. The early Ming imposed a series of sea bans (haijin, 海禁) that restricted or forbade private maritime commerce. At their height in the early sixteenth century, the bans effectively closed the Chinese coast to private trade. They were enforced unevenly, and smuggling was widespread, but the effect was to constrain Chinese maritime power and to allow the Portuguese, the Spanish, and the Dutch to enter the East Asian maritime world. The Portuguese established themselves at Macau in 1557; the Spanish at Manila in 1571; and the Dutch at Batavia in 1619.

The Late Ming Opening and the Silver Age

The Ming sea ban was progressively relaxed from the mid-sixteenth century, and the late Ming saw a major revival of Chinese maritime commerce. The single-whip tax reform of the 1580s and 1590s converted most tax obligations to silver, creating a strong incentive to allow the silver-bearing trade. The Spanish galleon trade at Manila carried Chinese silk, porcelain, and tea across the Pacific in exchange for American silver; the Hokkien and Teochew merchant communities established themselves throughout Southeast Asia; and Chinese junks dominated the intra-Asian trade. The deeper treatment of the late imperial monetary system is in the history of currency and commerce, and the goods that moved by sea are detailed in the history of what was traded on the Silk Road.

The Qing Canton System and the Nineteenth-Century Crisis

The early Qing attempted to manage the maritime frontier through restrictions rather than an outright ban. The Kangxi emperor (r. 1661–1722) lifted the ban in 1684, but the Qianlong emperor (r. 1735–1796) imposed the canton system in 1757, restricting European trade to the single port of Guangzhou and requiring all foreign merchants to deal with the Cohong merchant guild. The system allowed a substantial maritime trade while keeping foreign merchants under Chinese supervision.

The canton system worked reasonably well for most of the eighteenth century. The British East India Company, the Dutch VOC, the French, and the Americans operated under the system, and the trade in tea, silk, and porcelain was substantial. The system came under increasing pressure in the late eighteenth and early nineteenth centuries, as British demand for Chinese tea outstripped British willingness to pay in silver, and the British East India Company began to develop the opium trade in India as an alternative currency. The opium trade, conducted largely through smuggling, reversed the flow of silver and contributed to the fiscal crisis of the late Qing.

The breakdown of the canton system, the Opium Wars of 1839–1842 and 1856–1860, and the unequal treaties that followed were the beginning of the end of imperial China. The history of the fall of imperial China takes up the nineteenth-century crisis in detail.

The Legacy

The maritime trade of imperial China was, in the long run, one of the most important factors in the formation of the modern world economy. The Chinese demand for silver drove the trans-Pacific and trans-Atlantic silver flows; the Chinese supply of silk, porcelain, and tea was the foundation of the European and American trading companies; and the Chinese diaspora in Southeast Asia became one of the most important commercial networks in the modern world. The contemporary Chinese maritime economy has deep roots in the maritime trade of the Song, Ming, and Qing.