Ethnic political mobilization has become more pervasive in Nigeria since the 1990s. Against the backdrop of a conceptual framework that locates ethnicity as historically cumulative and ethnic interests as essentially contested, and with a focus on the recent form and character of ethnicity, this article analyses the changing patterns of ethnic politics in the country in terms of the arenas or levels of mobilization, the objectives of ethnic movements, and the strategies adopted in the ethnic struggles. The pervasiveness of ethnic politics in the country is taken to be symptomatic of the aggravated crisis of legitimacy that has engulfed the state, and is explained in terms of the proven efficacy of the ethnic strategy, the weakness of alternative identities and political units, the prevailing milieu of lawlessness that has enveloped the country's political landscape, and the inability of the state to act as an effective agency of distributive justice.