Lois Cassatt was the niece of James Buchanan, the fifteenth President of the United States. In 1868 she married Alexander J. Cassatt of Haverford, Pennsylvania, an engineer, collector and later President of the Pennsylvania Railroad, who was the brother of the Impressionist painter Mary Cassatt and J. Gardner Cassatt, an American financier.
On 3 April 1883 Alexander and Lois Cassatt approached Whistler about painting the latter's portrait, although Mary Cassatt had initially recommended Renoir. Whistler, whom Lois Cassatt described as 'most polite & most curious looking', arranged to start the following day. Whistler suggested Lois pose in riding habit, although she would have preferred evening dress. Arrangement in Black, No. 8: Portrait of Mrs Cassatt y250 was painted at 13 Tite Street, Chelsea. Lois Cassatt told the Pennells in June 1919, 'We spent every morning from 11-1 in the studio... It was an ordeal for me as you can imagine standing so long, but the time passed pleasantly and quickly... [once] from something I said Whistler took it that I did not consider it a likeness, nor do I, but he replied, 'After all it's a Whistler''. Whistler himself later admitted 'it is not a striking likeness' (GUW #09014). According to the Pennells, Cassatt paid for the portrait before leaving for America in April 1883. However, it was not finished and sent off until 1886/1887.
Whistler gave The Chelsea Girl y314 to the Cassatts as a present on the delivery of Arrangement in Black, No. 8: Portrait of Mrs Cassatt. The Cassatt's son Edward came to own both paintings.
Pennell, Elizabeth Robins, and Joseph Pennell, The Life of James McNeill Whistler, 2 vols, London and Philadelphia, 1908 ; Sweet, Frederick A., Miss Mary Cassatt: Impressionist from Pennsylvania, Norman, 1966; Young, Andrew McLaren, Margaret F. MacDonald, Robin Spencer, and Hamish Miles, The Paintings of James McNeill Whistler, New Haven and London, 1980 ; Matthews, N. M. (ed.), Cassatt and her Circle: Selected Letters, New York, 1984; Matthews, N. M., Mary Cassatt: A Life, New York, 1994.
Mathews, Nancy Mowll, 'Mary Cassatt', The Grove Dictionary of Art Online, ed. L. Macy; Genealogy Website; The Correspondence of James McNeill Whistler, 1855-1903, edited by Margaret F. MacDonald, Patricia de Montfort and Nigel Thorp. University of Glasgow, 2003.