The Irish narrative upon which WBY builds is the tale contained in the medieval Book of Leinster, the Aislinge Oenguso. However, the resultant poem constructs on this foundation a story and treatment that are in significant respects original rather than traditional. Interest in the narrative materials of the Tain was common among WBY's Irish contemporaries, and it may be significant that WBY chooses here to write a story about a time after that narrative's events, referring to these glancingly as ‘the great war Over the White-Horned Bull and the Brown Bull’. On its first periodical publication, the poem was noticed in the pages of The Speaker as being ‘a fine and characteristic piece’ by WBY. WBY made some revisions to the text for A selection from the poetry of W.B. Yeats, which were not carried forward to subsequent collected editions.