The Tong Wars was a series of violent disputes between rival Chinese tong factions that occurred in the "Chinatowns" of various American cities from the 19th to early 20th centuries. Tong organizations, employing salaried "hatchet-men", fought in Chinatown alleys and streets over the control of opium, prostitution, gambling, and territory.
During the 1850s, 25,000 Chinese immigrants came to California, many of them as temporary workers looking to acquire money during the Gold Rush or as laborers for major infrastructure projects such as railroad-building. During the 1850s and 1860s, there was very little violent crime in San Francisco's Chinatown, with crime being limited to lotteries and gambling (practiced by between 16% and 40% of Chinese, with between 10% and 20% being far-gone addicts), opium smoking, prostitution of slave-girls, and minor thievery. The Chinese enjoyed a relatively peaceful existence until the time of the American Civil War, when thousands of Chinese laborers were hired to help build the First Transcontinental Railroad. Nativist groups began to scapegoat the Chinese for mysterious fires which were actually ignited by groups like the Knights of Labor, a labor union federation which believed that the Chinese were being used as cheap alternative labor to replace white (and especially immigrant, i.e. Irish) labor and drive down their wages. The Panic of 1873 and the ensuing Long Depression intensified anti-Chinese sentiment, as did the outbreak of illnesses in Chinatown. Anti-Asian parties such as the People's Protective Alliance, People's Reform Party, and Anti-Chinese Party began to spring up, and eventually the Irish-dominated Workingmen movement. The Six Companies arose to represent practically all Chinese in California, attempting to help the Chinese move between their homeland and America, as well as to protect their community from racist hoodlums. While the Six Companies focused their efforts on the nativist groups, and as the San Francisco Police Department's "Chinatown Squad" grew lax after many years of little to no violence, immigrants such as Low Yet founded criminal organizations such as the Chee Kung Tong. The Tongs consisted mostly of American-born Chinese, while also hiring Japanese, Filipinos, and even a few whites. By 1854, the Chee Kung, the Hip Yee Tong, and the Kwong Duck Tong began to flourish in California, and these organizations engaged in racketeering, taking over illicit enterprises such as prostitution, gambling, and opium trafficking.
From the 1850s to 1870s, the Six Companies failed to battle the tongs, which grew exponentially around 1880. In 1878, the Long Zii Tong and Hop Wei Tong went to war as the ambitious Mai Ling murdered her husband, Long Zii, and led her organization on the warpath against Father Jun's Hop Wei, allying with the Fung Hai Tong. The war, and the large number of Chinatown murders that resulted, energized nativist sentiment, leading to the Tongs fighting both each other and the Workingmen movement. By the year's end, the Long Zii incorporated the Jiang Yao Tong into their ranks and eliminated the Suey Sing Tong, while the Hop Wei struggled against both the Long Zii and law enforcement.
The dozens of San Francisco tongs warred over matters as trivial as ownership of slave girls, as there were very few Chinese female immigrants to the United States at the time. The Hop Sing Tong and Suey Sing Tong engaged in fierce warfare from 1880 to 1913, while the Bo Leong Tong warred with the Bo On Tong, and both sides dragged their allies into the conflict. The Do On Tong and Suey Sing Tong came to be known as the bloodiest tong organizations; however, never did a single tong gain supremacy over all the others.
By the turn of the 20th century, the Chinese Exclusion Act, the militarization of the police, Donaldina Cameron's crusade against sexual slavery in Chinatowns, Chinese community mobilization against the tongs, and the destruction of San Francisco in a 1906 earthquake led to the end of the Tong Wars. The San Francisco earthquake displaced the aging hatchet-men to cities such as Chicago and New York, where the wars continued for another ten to twenty years. San Francisco experienced its last tong-related murder in 1921, and the last brothel raid occurred in 1925.