The history of the German language in America at the turn of the 20th century is one riddled with both praise and xenophobia (via Re-imagining Migration). Before World War I, the large German population in America was fairly respected and schools were even opened to teach the language (via EducationWeek). During and after the war, however, anti-German sentiments exploded as the language and culture were suppressed and, in some cases, people were even horrifically attacked and murdered for speaking the language (via History.com). As the German identity largely receded during the 1910s and early 1920s, more remote places like Hustisford, Wisconsin became ever more entrenched in their decades-old way of life. 

According to NPR not only were there many households that spoke both German and English, but some in this particular town even forbade the latter altogether. Where immigrant communities often become at least partly bilingual within two or three generations, it took around five generations before many of these families regularly spoke English (via Mental Floss). Ironically not only did their mother-tongue survive during this period, but many English-speakers of the town learned German themselves in order to adapt.