ABSTRACT: In the 1940s and 1950s, a group of Western educated young men from Idoma Division, colonial Nigeria, under the organizational canopy of the Idoma Hope Rising Union (IHRU) mobilized to reclaim what they believed was the diminishing honor of their ethnic group. This honor was defined in strictly patriarchal terms. The precursor to this activism is a colonial history of real and perceived humiliations and oppressions, as well as an alleged gang-up of internal and external actors against the Idoma. The young men targeted all suspected agents of the Idoma’s colonial humiliations: European colonizers, corrupt, dishonorable chiefs, Igbo traders and contractors, Hausa and Idoma tax scribes in the colonial bureaucracy— in short all those who purportedly denied the Idoma their due and prestige. Later, when the IHRU moved its operations to Northern Nigerian cities, where many Idoma young men and women were migrating to, the IHRU members initiated a campaign against what they saw as the dishonorable presence of Idoma prostitutes in cities. This gendered cultural vigilantism in the name of ethnic honor provoked fierce infighting within the IHRU, producing a camp of moderate, more established IHRU members, and another of younger, less secure, and less tolerant members. The ensuring debates and actions betray the intersection of male interests, aspirations, and minority sensibilities on the one hand, and contested idioms of ethnic moral values on the other. The paper argues that this long, “home” and “diaspora” struggle for the reclamation of ethnic honor is a window into the peculiar anxieties of patriarchy, ethnic politics, colonial modernity, and gendered notions of ethnic honor in the late colonial period.