There was a time when “a trade war with China” meant real war. During the 1800s, Britain was spending millions on Chinese silk, tea and porcelain, and wanted China to play fair by buying British goods in return. Rebuffed by the Qing Imperial court, the British tapped into a profitable underground demand for opium, imported cheaply from their Indian territories. When Chinese officials tried to stop the traffic, Britain launched the Opium Wars, which ended in 1860 with foreign armies besieging Beijing and forcibly opening up China to international trade.

Within a few years British merchants had established bases in eastern China, and began eyeing untapped markets in the country’s vast interior. But transporting goods inland was slow, unreliable, and expensive: roads were rough and prone to banditry, the rivers full of rapids and pirates, and transport taxes made the cost of British goods uncompetitive.

Looking for a backdoor into China, Britain homed in on the remote southwestern province of Yunnan. British India and Yunnan were separated by just one country – Burma (now known as Myanmar) – which Britain already had its hooks into, following victories in two Anglo-Burmese wars. Yunnan’s mountainous border with Burma was porous, crossed year-round by caravan trains transporting gemstones and raw cotton into China.

Unfortunately, all trade had been suspended by civil war. In 1856 Yunnan’s long-persecuted ethnic Muslims had rebelled against Chinese authority in what the British called the Panthay Uprising. Yunnan became a battleground as Imperial forces fought to stop the Panthays from turning the province into an independent Islamic state.

But it would take more than a war to deter Victorian adventurers. If routes between Burma and Yunnan were blocked, perhaps a British expedition could unblock them and negotiate for a favorable trade deal with whichever side won.

In January 1868 an expedition assembled at Bhamo, a Burmese market town just 30 miles fro