Theories of metaphor must account not only for embodied universals but also for systematic sociocultural variation. Although recent scholarship has highlighted the role of context in metaphor production, the extent to which intersecting macro-social variables shape metaphorical source-domain choice remains underexplored. This study therefore tests the hypothesis that metaphorical source-domain selection is systematically associated with group-level social identity by examining how NATIONHOOD is conceptualised in Nigerian presidential discourse and whether these choices correlate with ethnicity, region, and religion. Using CORNIPS, a 65-year diachronic corpus of Nigerian presidential speeches, and hierarchical log-linear analysis, the study finds that ethnicity emerges as the primary predictor of metaphorical choice. Specifically, leaders from the historically dominant Hausa-Fulani group show a marked preference for metaphors of personification and conflict (NATION AS PERSON, NATION AS WAR), while a minority-group leader favours metaphors of inclusion (NATION AS FAMILY). This suggests that these speakers draw on distinct cognitive models, notably NATION-AS-PERSON/ORGANISM-UNDER-THREAT and NATION-AS-KINSHIP to conceptually structure the nation. Although the findings are situated within specific historical and individual contexts, the study nevertheless shows that metaphorical cognition is meaningfully shaped not only by embodied experience but also by social identity, political history and cultural context.