The Scottish-born Mosman studied under Francesco Fernandi, il Imperiali, in Rome 1732-35, when he would have seen his master's Erminia carving her lover Tancred's name on a Tree (private collection, see A.M. Clark, Studies in Roman Eighteenth Century Painting, ed. E.P. Bowron, 1981, p. 87. fig. 102). The present picture, which may have been executed in Rome, directly follows Imperiali's format. Mosman's huge canvas of the same subject was extended on both sides to hang in Patrick Duff's saloon at Culter House (exhibited Edinburgh, S.N.P.G., atrons and Painters, 1989, no. 69).
The subject is taken from Tasso's Gerusalemme Liberata, Canto 7, Stanza 17, lines 1-14, and the pose of Erminia is thought to have inspired that of Reynolds' Mrs Lloyd (private collection).