Moore had not taken the United Irish oath with Emmett and Hudson, and he played no part in the republican rebellion of 1798, or in the conspiracy for which Emmett was executed in 1803. Later, in a biography of the United Irish leader Lord Edward Fitzgerald (1831), he made clear his sympathies, not hiding his regret that the French expedition under General Hoche failed in December 1796 to effect a landing. To Emmett's sacrifice on the gallows Moore pays homage in the song "O, Breathe Not His Name".