http://www.archives.gov/publications...bellion-1.html U.S. Marines in the Boxer Rebellion (1900)
In 1900 a crisis erupted in China as the "Boxers" increased their resistance to foreign influence and presence. By the end of the nineteenth century, several countries had already established spheres of influence in China. In the fall of 1899, Secretary of State John Hay wrote that the United States, a late arrival, wanted to maintain an "open door policy" in China. If the Boxers succeeded in pushing the United States and other foreign countries out, this newly opened door could soon be shut.
Discontent with foreigners had been on the rise in China since 1898, when the "I Ho Ch'uan" (Society of "Righteous and Harmonious Fists") began gaining popularity in a province in northwest China. This group commonly referred to as "Boxers" opposed foreign influence and was strongly anti-Christian. The group's numbers swelled with farmers and other workers who were affected by droughts that had come on the heels of devastating floods. Boxers began harassing Chinese Christians and foreign missionaries. As Boxer activity spread to several provinces, provincial leaders and the Chinese imperial court were inconsistent in their stances. Authorities sometimes fought to protect foreigners and Christians and at other times chose to do nothing at all. Tzu Hsi, the empress dowager of the Manchu Dynasty, was publicly "anti-Boxer."
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The United States and seven other countries - Austria-Hungary, France, Germany, Great Britain, Italy, Japan, and Russia-all had interests in China. These eight foreign powers also maintained legations in the Legation Quarter of Peking.
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