The subject of that statue, William Smith O'Brien, had been sentenced to death for high treason just twenty-two years earlier. That the city was now raising a marble figure in his honour, in a prominent public location, was understood by everyone present as something more than a civic gesture. It was, the Irish Times reported the following day, the first time in seventy years that Dublin had publicly honoured a man whose claim to that honour was his devotion to the Irish national cause.

O'Brien was born in 1803 into the Protestant nobility, and traced his lineage back to Brian Boru. He became a leader of the Young Ireland rebellion of 1848, a failed insurrection that resulted in his being sentenced to be hanged, drawn, and quartered, though the sentence was later commuted. He died in 1864, and within a few years a committee led by John Martin and John Blake Dillon, both veterans of the same radical mid-nineteenth-century politics, was gathering subscriptions from across the political and religious spectrum to fund a monument. Dublin Corporation granted permission for the site at the junction of Sackville Street and D'Olier Street in 1867. The sculptor chosen was Thomas Farrell RHA, then based on Lower Gloucester Street and considered one of the most prominent sculptors of his day. Working in marble, Farrell depicted O'Brien in an ordinary frock coat, high-buttoned waistcoat and pantaloons, arms folded, weight shifted onto one leg, in what contemporary observers described as an easy and natural pose. The inscription on the base recorded his birth date, his death, and the fact of his death sentence for high treason, in that order.

The statue currently stands on O'Connell Street, having been moved from its original position at the Sackville Street and D'Olier Street junction. A 1929 report by the Streets Section of Dublin Corporation recommended the relocation, citing traffic congestion at O'Connell Bridge as the reason, and it was repositioned to a site near the centre of O'Connell Street, approximately twenty feet south of the junction with Lower Abbey Street. It is easy to walk past without pausing, set as it is among the larger monuments on that busy thoroughfare, but the inscription is worth reading closely. The phrasing, which leads with the death sentence rather than any political office, was a deliberate choice, and it tells you something about what the committee understood they were doing when they put it there.