The sitter, Principessa Giacinta Orsini was the daughter of Prince Domenico Orsini and his wife née Principessa Anna Erba Odescalchi: in 1757 she married Antonio Buoncompagni Ludovisi, Duca d'Arce, but died in childbirth two years later. Although only eighteen at the time of her death, the Princess had already attracted attention as a poetess and belonged to the Roman literary society, the Accademia dell'Arcadi, where she was styled 'Euridice Aiacense'. The books on the clavichord, Petrarch and Anacreon, testify to her interest in poetry and the meticulously described scene in the background is a further allusion to this, as the fountain of Hippocrene was sacred to the Muses and said to inspire poetry (Clark, ed. Bowron, p. 272).
Dated 1757-8 by Clark, the picture is the close contemporary of some of the finest of all Batoni's Grand Tour portraits, including those of John, Lord Brudenell (Boughton House) and Charles, 7th Earl of Northampton (Cambridge, Fitzwilliam Museum). Despite Batoni's technical mastery of costume painting, he painted relatively few portraits of women. In the sequence of these, this portrait follows those of a number of English visitors to Rome of 1750-1 (the Hon. Mrs. Thomas Barrett-Lennard, Lady Caroline Damer, Sarah, Lady Fetherstonhaugh and Mrs. Ulrick Fetherstonhaugh (Clark, nos. 127, 133, 133a, 155, 157 and 159)) and precedes two masterpieces of the following decade, the Georgiana, Countess Spencer and the Lady Mary Fox (Clark, nos. 269 and 323). Despite his pre-eminence among Roman painters Batoni received relatively few Italian portrait commissions: apart from the 1768 Duchessa Sforza Cesarini (Birmingham, City Art Gallery), the only female portraits among these are of the last phase of his activity, 1785-6; the Thyssen Contessa di San Martino, the Edinburgh Principessa Giustiniani and the untraced Marchesa Brignole (Clark, nos. 326, 458, 456 and 463). While the Principessa Giustiniani has been compared with slightly later works by the young Jacques-Louis David, this picture, so characteristic of the painter in its meticulous technique, is the most explicit literary portrait in Batoni's oeuvre.