This article presents an analysis of a file concerning the racial assessment and contestation of a denaturalisation proceeding held in the Demorazza collection at the Central State Archive in Rome. The file relates to the naturalisation and subsequent denaturalisation of Giuseppe Blinderman, a ‘stateless’ individual of Jewish origin (first formerly Russian and then formerly Italian) in Fascist Italy. Focusing on Blinderman’s actions and skills in shaping his public identity according to the authorities’ criteria, the article aims to reconstruct Fascist denaturalisation policies and assess the relationship between the event triggered by the anti-Semitic denaturalisation measure and the previous naturalisation process. As with most cases of denaturalisation due to anti-Semitic legislation, the latter also occurred under the Fascist regime, but before the turning point of 1936–38. Adopting a bottom-up perspective, the article thus raises questions about the continuities and discontinuities represented by Fascism and, particularly, with regard to Fascist anti-Semitic policies on citizenship, revealing the interplay between ‘race’ and ‘nativeness’.