"Where the foreleg of King Billy's horse pawed the air Mrs Breen plucked her hastening husband back from under the hoofs of the outriders": Dennis Breen's heedless half-mad pursuit of justice nearly reduces him to roadkill under the hooves of the viceregal cavalcade, much as the hooves of the Protestant conqueror's steed reduce him to battlespoil.
Joyce's prose artfully contrives to crush the Catholic Breen between the actual horses pulling the carriages of Ireland's British rulers and the symbolic horse carrying its most decisive British conqueror, making his arrested motion a vivid image of colonial paralysis. In a paper titled "Yeats, Joyce and the Easter Rising: Textual and Contextual Significance of 'U.P.' in Ulysses," Kazuhiro Doki makes this point: "Needless to say, William III, who defeated James II in the Battle of the Boyne 1689 [sic] and paved the way for Protestant Ascendancy, is a symbolic figure for the final stage of the English colonization of Ireland. Therefore, he marks one end of the history, while the viceroy marks the other. Breen, who is closed in from both sides with their horses 'hoofs,' can be seen as an allegorical figure of colonial Ireland at the turn of the century, or in Joycean terms, as a picture of paralysis" (40).
Joyce had already once used this statue to symbolize the paralyzing subjection of a colonial city. In The Dead, Gabriel Conroy gracefully tells the story of his grandfather's horse Johnny, who spent his days walking round and round to turn the wheel in Patrick Morkan's starch mill. And "That was all very well; but now comes the tragic part about Johnny. One fine day the old gentleman thought he'd like to drive out with the quality to a military review in the park." Like the Dubliners bowing and scraping before the viceregal carriage, Morkan puts on his best attire for "the quality" at the military review, and harnesses his old horse to his carriage. "And everything went on beautifully until Johnny came in sight of King Billy's statue: and whether he fell in love with the horse King Billy sits on or whether he thought he was back again in the mill, anyhow he began to walk round the statue," over and over in his accustomed pointless repetition. The "tragic part" of this funny story is that Irish men and women revolve in the same soul-killing orbit.
Stephen has associated fine race horses with English nobility and Irish Ascendancy gentry in Nestor. Bloom too has his thoughts about the horsey set, in Lotus Eaters, Lestrygonians, and Circe.