In 1923, the state of Illinois made “American” the official state language rather than English. So. What happened there? Well, it’s no use pointing fingers just at Illinois, for one thing...
Back in 1923, Montana Representative Washington Jay McCormick attempted to pass a bill changing the official language of the entire United States to “American” rather than English. Alas, the bill failed (and, perhaps coincidentally, McCormick soon afterwards lost his seat), but it had nevertheless found some backing. Lo and behold, later that year, Senator Frank Ryan of Illinois picked up the campaign in his home state.
It was there, in Illinois, it found the backing of a large number of Jewish and Irish-heritage politicians who saw Ryan’s bill as a means of not only reinforcing their pride in America, but of showing their distaste for the UK’s treatment of both Palestine (a British mandate at the time) and the newly-realised Irish Free State (later the Republic of Ireland). Ultimately, Illinois became one of the first US states to adopt official language legislature.
Opinions and feelings changed over time, however, and the decision was quietly reversed in 1969.