thousand civilians, British prime minister Herbert Henry Asquith took revenge, locking up tens of thousands of German and Austro-Hungarian “enemy aliens” in England.

The same year, the British Empire extended internment to its colonies and possessions. The Germans responded with mass arrests of aliens from not only Britain but Australia, Canada, and South Africa as well. Concentration camps soon flourished around the globe: in France, Russia, Turkey, Austro-Hungary, Brazil, Japan, China, India, Haiti, Cuba, Singapore, Siam, New Zealand, and many other locations. Over time, concentration camps would become a tool in the arsenal of nearly every country.

In the United States, more than two thousand prisoners were held in camps during the war. German-born conductor Karl Muck, a Swiss national, wound up in detention in Fort Oglethorpe in Georgia afterfalse rumors that he had refused to conduct “The Star-Spangled Banner.”

Unlike earlier colonial camps, many camps during the First World War were hundreds or thousands of miles from the front lines, and life in them developed a strange normalcy. Prisoners were assigned numbers that traveled with them as they moved from camp to camp. Letters could be sent to detainees, and packages received. In some cases, money was transferred and accounts kept. A bureaucracy of detention emerged, with Red Cross inspectors visiting and making reports.

By the end of the war, more than 800,000 civilians had been held in concentration camps, with hundreds of thousands more forced into exile in remote regions. Mental illness and shattered minority communities were just two of the tolls this long-term internment exacted from