The daughter of Ignatius Begg of Belrea in Roscommon; in 1797 she married Patrick Dillon, eleventh earl of Roscommon.

REFERENCES TO Barbara Dillon, countess of Roscommon [née Begg]:

Thomas Creevey to Elizabeth Ord, 19 January 1821 in The Creevey Papers: A Selection from the Correspondence & Diaries of the late Thomas Creevey, M.P. (London: John Murray, 1903)