I am sure I had more than one teacher talk about the Boxer Rebellion, but I recall nothing about it or even hearing about it (I probably skipped that section of the text book and tuned out that portion of lectures) until EB Sledge made mention of it in China Marine, so I looked it up.
The Boxer Rebellion — what I understand in my brief reading — was an uprising by 1000s of Chinese who grew tired of Christian influences. Basically, it was these folks (called Boxers) who rose up against Chinese Christians and foreigners to expel them. Eventually, the Chinese Empress of the time gave her support and diplomats, Chinese Christians and foreigners were besieged. “A state of war” existed between the Chinese forces and foreign armies, including nearly 500 US Marines and more than 1,000 US enlisted soldiers overall. There were periods of intense combat that left several US Soldiers killed and earned many Medals of Honor. I had no idea. I knew about The Roughriders charge during the Spanish American War of the 1890s, but not of our battles in the Boxer Rebellion in 1900.
1000s of people died over several years, before the rebellion was put down by a combination of internal forces and foreign soldiers. But the rebellion had long-term consequences in that foreign powers decided to focus more on the emperors and less on the people, to stop any attempts to colonize China, and to turn attensions elsewhere. Meanwhile, the Chinese turned inward and were less welcome to foreign influences.