This paper revisits a classic question for scholars of government and politicians: how is the behavior of cultural or ethnic groups affected by the formal institutions that regulate their rights? While the literature has demonstrated that state-sanctioned discrimination or forced assimilation into a majoritarian identity often produces backlash among minority members, I study the consequences of accommodating minority rights, focusing on one important dimension: the status of minority language. I exploit a regional linguistic reform in post-transition Spain: in 1986 the Spanish province of Navarra allocated municipalities into one of three linguistic zones, each with a different degree of normalization of the Basque language in the public sphere. I study the effects of differential linguistic rights on the identity choices of Basque and Spanish speakers, the making of group boundaries, and the forms of political participation until today. With granular sub-municipal data and a Geographic RDD, I find that crossing the administrative border of the bilingual zone increases the vote shares of Basque nationalist parties, at the expense of traditional Spanish parties. With a Difference-in-Differences design and historical election data, I then study how the reform induced diverging patterns in voting behavior across formerly politically homogenous areas. Exploring the causal mechanisms, I find evidence of attempts at reshaping the public space by translating street names into Basque. I then track identity choices across generations with data on Basque names and surnames in municipal election lists and with surveys on linguistic preferences.