In the contemporary debate on language and national identity in the US, those who are in favor of a constitutional amendment declaring English the offi cial language of the country believe that speaking the same tongue is crucial for the political and cultural unity of the nation. Those who are against the amendment claim that dictating by law the linguistic Americanization of immigrants is incompatible with American multiculturalism. Both sides ground their ideas in the language ideology and politics of the Founders and interpret in opposing ways the absence of a statement on language in the Constitution. What Americans believed about the importance of a national language for the new nation at the turn of the eighteenth century sti...