Maritime East Asia (1840–1851 CE): Opium Wars, Rebellion, and Isolation

Between 1840 and 1851 CE, Maritime East Asia—encompassing lower Primorsky Krai, the Korean Peninsula, the Japanese Archipelago south of northern Hokkaido, Taiwan, and southern, central, and northeastern China—faces intense internal crises, major rebellions, and the challenge of Western intrusion, resulting in profound shifts in regional stability and political dynamics.

China: The First Opium War and Unequal Treaties

After a decade of ineffective anti-opium campaigns, the Qing government adopts severe measures in 1839 to eradicate the opium trade. The emperor dispatches Commissioner Lin Zexu to Guangzhou, where Lin dramatically seizes and destroys approximately twenty thousand chests of illicit British opium. The British retaliate forcefully, initiating the First Opium War (1839–1842).

China, unprepared and severely underestimating British military capabilities, suffers a humiliating defeat. The resulting Treaty of Nanjing (1842)—signed aboard a British warship—marks the first of China's infamous "unequal treaties."Under its terms, China cedes Hong Kong to Britain, opens five treaty ports to foreign trade, grants extraterritorial rights to British nationals, fixes low tariffs favorable to British interests, and pays a substantial indemnity. This treaty significantly weakens Qing authority, initiating a prolonged period China later terms the "Century of Humiliation."

The Taiping Rebellion

Economic distress, compounded by natural disasters such as severe droughts, floods, and famines, fuels widespread social discontent. In this volatile climate, the largest rebellion in modern Chinese history—the Taiping Rebellion—erupts in 1851 under the leadership of Hong Xiuquan, a village teacher influenced by Protestant beliefs and anti-Manchu sentiment.

Hong proclaims the establishment of the Heavenly Kingdom of Great Peace (Taiping Tianguo), advocating radical social reforms, including communal land ownership, abolition of slavery and concubinage, rejection of opium use, and the elimination of traditional practices like footbinding and ancestor worship. Despite capturing major cities such as Nanjing and advancing toward Tianjin, the movement ultimately alienates the Confucian scholar-gentry and fails to sustain a stable administration. Its radical ideology, internal conflicts, and external pressure from foreign powers assisting Qing forces lead to its eventual suppression, though not before massive devastation and the loss of millions of lives.

Japan: Defensive Reforms and Increased Vigilance

In Japan, the Tokugawa shogunate becomes increasingly alarmed by Western powers’ successful encroachments into China. Seeking to avoid similar exploitation, the bakufu undertakes additional economic reforms aimed at strengthening Japan's defenses against potential Western threats, emphasizing isolationist policies to resist external influence.

Joseon Korea: Intensified Isolation

Joseon Korea responds to these regional threats by intensifying its isolationist policies. Awareness of China's humiliating defeat in the Opium War reinforces Korea’s determination to resist all Western overtures, which had previously been banned after harsh reactions against Western, especially Catholic, influences in earlier decades. This intensified isolation lays groundwork for future conflicts as Korea struggles to maintain its traditional structures amid increasing external pressures.

Legacy of the Era: Humiliation, Rebellion, and Isolation

Thus, the period from 1840 to 1851 CE leaves a profound legacy in Maritime East Asia marked by China’s deep humiliation following the Opium War and the upheaval of the Taiping Rebellion, Japan's defensive isolationism, and Korea's reinforced seclusion. These developments set the stage for significant transformations in the region's political, social, and international relations.

China is forced to cede Hong Kong to Britain in 1842. 

Britain is also granted extraterritoriality.

Other Western Powers, such as France and the United States, will soon extract similar privileges from China.

Under the 1842 Treaty of Nanjing that ends the Opium War, five Chinese ports—Guangzhou (Canton), ...

The Treaty of Nanking, an unequal treaty between Britain and Qing dynasty China, ends the First Opium War on August 29, 1842, and establishes Hong Kong as a British colony until 1997.

The Chinese ports of Amoy, ...

...Fuzhou (Foochow), ...

...Ningbo (Ning-po), and ..

...Shanghai—are opened to British commerce and residence.

The Hong Kong Police Force, the world's second, Asia's first modern police force, is established on April 30, 1844, by Captain Charles Elliot, twelve weeks after the British landed in Hong Kong.

The first chief of police is Captain William Caine, who also serves as the Chief Magistrate.

The United States signs the Treaty of Wanghia with the Chinese Government, the first ever diplomatic agreement between China and the United States, on July 3, 1844.

Following passage by the U.S. Congress, it will be ratified by President John Tyler on January 17, 1845.

It is considered an unequal treaty by some Chinese.

The treaty is named after a village in northern Macau where the temple is located, called Mong Ha or Wang Hia.

The United States is represented by Caleb Cushing, a Massachusetts lawyer dispatched by President John Tyler under pressure from American merchants concerned about the British dominance in Chinese trade.

A physician and missionary, Peter Parker, serves as Cushing's Chinese interpreter.

The Qing Empire is represented by Keying, the Viceroy of Liangguang, who holds responsibility for the provinces of Guangdong and Guangxi.

The treaty is modeled after the Treaties of Nanking and the Bogue between the UK and China, but differs in being more detailed.

Among other things, it contains provisions for:

    Extraterritoriality, where Chinese subjects will be tried and punished under Chinese law and American citizens will be tried and punished under the authority of the American consul or other public functionaries authorized to this effect
    Fixed tariffs on trade in the treaty ports
    The right to buy land in the five treaty ports and erect churches and hospitals there
    The right to learn Chinese by abolishing a law which hitherto forbade foreigners to do so
    The U.S. receives most favored nation status, resulting in the U.S. receiving the same beneficial treatment China has given to other powers such as Britain, and receives the right to modify the treaty after twelve years

The United States also grants the Qing empire powers to confiscate American ships if operating outside treaty ports and withdraws consular protection in cases where American citizens are trading in opium under articles 3 and 33, respectively.

Furthermore, the U.S. agrees to hand over any offenders to China.