This article examines the politicisation and limitations of Afrodiasporic humour in Elnathan John’s 2019 text: Be(com)ing Nigerian. Although most literary commentators tend to categorise this satirical guide as a novel, it does not follow the plot structure of a conventional prose narrative. Rather, John models his text on ethics and aesthetics of Onitsha pamphlet literature, a popular culture tradition which flourished during the colonial epoch. My central argument is that John’s satirical critique of Nigerian national identity does not only elicit the reader’s laughter, but also challenges his fellow citizens to recalibrate their cultural ethics, in order to achieve a self-improvement agency both individually and collectively. In providing this self-improvement guidance, John effectively invests the reader’s aesthetic sensibility with an ideological hermeneutic, which underpins, and so enables, a vicarious satirical critique of what it means to be Nigerian in different socio-political contexts. I therefore demonstrate how John deploys colonial and Eurocentric clichés, biblical imagery and rhetoric, irony, sarcasm, parody, and hyperbole to satirise the constructedness, complexities, and ambiguities of a Nigerian identity born out of British colonialism and post-independence misrule of both military and civilian dictatorships. For insofar as form dialectically overlaps with theme, John’s self-improvement guide is ineluctably embedded with a satirical politics and poetics. That is, as a Nigerian diasporic writer who currently lives and works in Germany, John inhabits a transcultural space between the local and the global, from which he satirises both indigenous and Western values. I also contend that John’s transcultural ambivalence reveals the limitations of his Afrodiasporic humour, since Nigeria’s ethnic diversity implies cultural incommensurability and potential audience conflict. I then conclude by reflecting on how John’s satirical guide adumbrates the production, circulation, and critical reception of African postcolonial humour, a genre which remains largely undertheorised.