“Oxen of the Sun” is an episode in Ulysses which famously recapitulates the growth and development of the English language through the ages. As the narrative unfolds, we move from one canonical style of English literature to the next. Joyce’s ventriloquizing tour de force is in itself a challenge to the notion of ‘national literature’, showcasing the ability of a peripheral (Irish) writer to master a metropolitan tradition. As such, the episode involves a challenge to narratives of literary ownership, resting on the ability to appropriate the past. While the struggle over national literature is a crucial dimension of “Oxen of the Sun”, my paper focusses on Joyce’s engagement with the notion of national language itself. In particular, I pay attention to the opening and conclusion of the episode, which cast a shadow over the intervening succession of authorised English literary styles. Those passages consist respectively in a medley of pseudo-Gaelic and Latin, and a “frightful jumble” (dixit Joyce) of non-standard dialects of English. The embryonic growth of national literature, therefore, turns out to be framed by impure, heterogeneous linguistic forms, from which the standard, national language emerges, and into which it ultimately dissolves. Finally, I argue that the cattle raiding epic Táin Bó Cúailnge is a crucial intertext for the literary and linguistic cattle raid that is “Oxen.” By looking at the broader tradition of cattle-raiding poetry, I argue that the vestigial power of archaic cultural forms helps us think through the relation between conflicting literary temporalities.