It all started when a rejected civil servant in China decided what his country really needed was a clean break from Buddhism, Confucianism and sanity. So in 1844, Hong Xiuquan invented his own sect of Christianity by declaring himself the little brother of Jesus Christ. This gained him the loyalty of 30 million followers, who took on a dynasty that was over 250 years old.
His hat would have had to be at least twice that height for there to be any hope of victory.
The only equivalent we can imagine would be if those Hale-Bopp guys convinced the entire state of California to join the club and they stormed Washington, D.C. The cult army lost, of course, which is why we aren't discussing U.S./Heavenly Kingdom trade relations today. But the rebellion took the Qing Dynasty 34 years to completely defeat, and directly led to the version of China currently limbering up to kick the West's ass in the 21st Century.
Depending on who you ask, Hong looked like either a total dweeb or a character from Dynasty Warriors.
The problem was that the Qing Dynasty were so far over their heads with the rebels (not to mention several copycat rebellions) that they had to appeal to Britain and France for help, which they were thrilled to provide because it was the 1800s and the West was all up on that imperialism s**t. While helping the Qing defeat the rebels, the British Empire and France also helped themselves to whatever they liked along the way by launching the Second Opium War against the Chinese.