This article analyses several facets of the political path towards independence in Mauritania, and of the process of Arabisation that followed in the country, taking into account the influence exercised by different ethnic communities. In particular, this article will focus on the French administrative reforms of mid-1940s, that allowed political representation for colonies and legitimised competition among parties, and then on the early years following independence, when Ould Daddah imposed monopartitism and Arabisation through a consolidation of his power. This last process in particular elucidates abuses by traditional élites – mostly Arab and Berber – over resident blackMauritanian communities, whose claims for equality conflicted with the promotion of a national Arab identity. Primary sources used in this article include those of the French West Africa’s Archives in Dakar and of the Archives nationales d’outre-mer in Aix-en-Provence. This article’s analysis supports and draws comparisons with existing literature.