As prejudice against immigrants became widespread, a very tense situation developed for Americans of Italian and German ancestry. Italian Americans and German Americans faced discrimination, and thousands were interned because of fears they were disloyal.
What happened in theb period
During periods of heightened prejudice against immigrants, particularly during times of war or geopolitical tensions, groups with origins in countries perceived as enemies or as threats to national security often faced discrimination.
In the context of the sentence provided, Americans of Italian and German ancestry encountered discrimination due to widespread prejudices against these nationalities during certain historical periods, such as World War I and World War II.