In the mid-1850s, while the Qing government was embroiled in trying to quell the Taiping Rebellion (1850–64), the British, seeking to extend their trading rights in China, found an excuse to renew hostilities. In early October 1856 some Chinese officials boarded the British-registered ship Arrow while it was docked in Canton, arrested several Chinese crew members (who were later released), and allegedly lowered the British flag. Later that month a British warship sailed up the Pearl River estuary and began bombarding Canton, and there were skirmishes between British and Chinese troops. Trading ceased as a stalemate ensued. In December Chinese in Canton burned foreign factories (trading warehouses) there, and tensions escalated.

The French decided to join the British military expedition, using as their excuse the murder of a French missionary in the interior of China in early 1856. After delays in assembling the forces in China (British troops that were en route were first diverted to India to help quell the Indian Mutiny), the allies began military operations in late 1857. They quickly captured Canton, deposed the city’s intransigent governor, and installed a more-compliant official.

The second Opium War (1856–60), also known as the Arrow War or the Anglo-French War in China, was fought by Britain and France against China.

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