On February 17, 1918, the U.S. Department of Justice sent instructions to “war bureaus” throughout Michigan to arrest all German aliens who had failed to register. As a result, many of Michigan’s 80,000 German-born and 20,000 Austrian-born residents who had not registered with the government faced internment or deportation. This came in the wake of anti-German sentiment sweeping the nation after the declaration of World War I.
Source: Mich-Again’s Day