Images in the Heinz Archive, National Portrait Gallery, suggest that that the sitter in this portrait is Lady Bellamont. Russell executed pastels of both Lord Bellamont of Bellamont Forest, Cavan, Ireland (1738-1800) and Lady Bellamont, with her child, in 1784 , the same year as our work (see G.C. Williamson, John Russell, R.A., 1893, p. 140). Lady Bellamont is depicted in an identical costume as in the present work, looking straight ahead.
Lord Bellamont was Deputy Quartermaster General of the Forces in Ireland and Privy Councillor, Ireland from 1766-1773. He was created Earl of Bellamont in 1767. A notorious womaniser he eventually married Emily Fitzgerald, daughter of James, 1st Duke of Leinster on 20 August 1774. There were four legitimate daughters and one son Charles, who died aged 8 in 1786. A full-length portrait of the Earl of Bellamont by Reynolds is in the National Gallery of Ireland, Dublin and the companion of the Countess is in the Wernher Foundation, Luton Hoo.
The Bakers of Bayfordbury owned an important collection of paintings including a number of Kneller's famous Kit-cat Club portraits.