The Immigration Act of 1917 was a significant piece of legislation in the United States that aimed to restrict immigration. It established a literacy test for immigrants over the age of 16 and created a list of undesirable classes, including those with certain health issues, criminals, and people from specific countries, particularly in Asia. This act also introduced the concept of an "Asiatic Barred Zone," which effectively banned immigration from many Asian countries. Overall, the Immigration Act of 1917 marked a shift towards more restrictive immigration policies in the U.S., reflecting growing concerns about national security and cultural integration.