Lady Lucy Anne FitzGerald (5 February 1771 – 20 January 1851) was an Anglo-Irish political radical: a supporter, with her mother Lady Emily, of her cousin, the English Whig reformer Charles James Fox and, with her brother Lord Edward, of the republican and democratic Society of United Irishmen.
During the period she spent in Ireland from October 1796 to May 1797, she met many of Edward's republican friends, including Arthur O'Connor.
Her diaries also provide an important factual account of Edward's movements, as she spent a great deal of time with his wife Pamela.
Both of the women enjoyed French revolutionary songs and Irish jigs and shared in their support for the Society of United Irishmen.
Her friends interpreted her reaction of FitzGerald to the arrest of Arthur O'Connor as a sign she was in love with him, and his imprisonment in Kilmainham Gaol resulted in the hardening of her radical republican beliefs.