The son of Luke Gardiner, first Viscount Mountjoy, educated at Eton. After a second marriage to Lady Blessington in 1818 he traveled on the Continent with his wife and Count D'Orsay, residing in Naples and Paris.

REFERENCES TO Charles John Gardiner, first earl of Blessington:

Lord Byron to Thomas Moore, 24 May 1820 in Letters and Journals of Lord Byron 2 Vols (London: John Murray, 1830)

Augusta Leigh to Lady Byron, 11 January 1821 in Astarte: a Fragment of Truth concerning George Gordon Byron, sixth Lord Byron (London: Christophers, 1921)

Lord Byron to John Murray, 27 January 1821 in Letters and Journals of Lord Byron 2 Vols (London: John Murray, 1830)

Lord Byron to Thomas Moore, 2 April 1823 in Letters and Journals of Lord Byron 2 Vols (London: John Murray, 1830)

Lord Byron to the Earl of Blessington, 5 April 1823 in Letters and Journals of Lord Byron 2 Vols (London: John Murray, 1830)

Lord Byron to the Earl of Blessington, 6 April 1823 in Letters and Journals of Lord Byron 2 Vols (London: John Murray, 1830)

Thomas Creevey to Elizabeth Ord, 20 October 1834 in The Creevey Papers: A Selection from the Correspondence & Diaries of the late Thomas Creevey, M.P. (London: John Murray, 1903)

Countess of Blessington to Peter George Patmore, 15 April [1837] in My Friends and Acquaintance: being Memorials, Mind-portraits, and Personal Recollections of Deceased Celebrities of the Nineteenth Century; with Selections from their Unpublished Letters 3 vols (London: Saunders and Otley, 1854)