According to widely accepted wisdom, “national” groups within the nation-state belong to a different socio-political category than “ethnic” groups that emerged through immigration. As a consequence of this division, scholars have failed so far to examine if and how the relationships between established “national” groups impact on public representations of, as well as state responses to immigration-induced diversity. This paper examines the ways in which minority nationalism and its accommodation within the multi-nation state affect the (de)legitimization of multiculturalism in response to immigration. It theoretically develops and empirically illustrates four ideal-typical relations between established “national” groups and newcomers. The paper demonstrates that relations between different categories of groups and diversity accommodations are both theoretically plausible and empirically traceable.