In composing Pylades and Orestes West was heavily influenced by the neo-classical history paintings of Gavin Hamilton and Anton Raphael Mengs whom he had known during his studies in Italy between 1760 and 1763. He also looked for inspiration to the frescoes of Raphael and classical relief sculpture, notably the 'Orestes Sarcophagus' in the Villa Ridolfi, Rome, drawings from which he used to form the pose of his own figure of Orestes. West also revealed later that 'his mind was full of Correggio' when painting the present work, at least with respect to the colour of the figures' flesh' (quoted in von Erffa and Staley, p.261).

The early history of the picture is interesting. Apparently it was greatly admired in West's studio, even before it was exhibited, although of the many wealthy collectors who came to inspect it, none offered to buy it. However, in 1766, the year of its exhibition, Alexander Geddes (1737–1802) purchased the picture from West for 100 guineas, although by 1776 it belonged to the engraver and dealer Gerard Vandergucht (1696–1776), in whose posthumous sale it appeared the following year. By 1802 West had reacquired the picture, selling it once more, this time to the influential collector Sir George Beaumont. In 1826 Beaumont presented it to the National Gallery, making it the first picture by West to enter a public art gallery. It remained in the National Gallery until 1929, when it was transferred to the Tate Gallery.

Further reading: Helmut von Erffa and Allen Staley, 'The Paintings of Benjamin West', New Haven and London, 1986, pp.260–261, no.186 'Noble and Patriotic. The Beaumont Gift 1828', exhibition catalogue, National Gallery, London 1988, p.56, no. 13, reproduced in colour Martin Postle September 2000