The literacy test was a barrier to entering the country, not to citizenship. https://history.state.gov/milestones/1921-1936/immigration-act https://history.stat

The literacy test was a barrier to entering the country, not to citizenship. https://history.state.gov/milestones/1921-1936/immigration-act https://history.state.gov/milestones/1921-1936/immigration-a... And while that one didn't have a very large effect, the one that did block people from voting managed to filter out black people very well: https://metro.co.uk/2017/09/20/could-you-pass-this-test-given-to-black-people-registering-to-vote-in-america-in-1964-6941338/ https://metro.co.uk/2017/09/20/could-you-pass-this-test-give...