The nymph Callisto was the favourite of Diana, virgin goddess of the hunt. Jupiter, king of the gods, noticed her beauty and seduced her by disguising himself as Diana. Titian has painted the moment Diana forces Callisto to strip and bathe after hunting and discovers her pregnancy. At the goddess’s command Callisto is pinned down by her fellow nymphs and her clothes wrenched away, exposing her swollen belly. Callisto sprawls on the ground with legs and arms flailing. Titian shows her humiliating exposure and banishment from Diana’s chaste entourage.

The drama is heightened by Titian’s free and expressive brushwork. Voluptuous flesh is suggested in energetic and thick buttery strokes of paint. The contours of the figures dissolve as the thinnest of dragged brushstrokes are swept over the surface of the canvas, contributing to the sense of dynamism and movement. Trees sway, streaks of golden cloud swirl in the sky and the stone pier tilts disconcertingly. The unicorn pattern of the gold cloth hanging over the tree is worked wet-in-wet, with glittering impasto highlights. The cord at the upper edge of the canopy that secures the fabric to the branches is a simple streak of lead white paint that relies on our eye to give it meaning.

In the next part of the story, shamed Callisto is transformed into a bear by Jupiter’s jealous wife Juno, but is later immortalised by him as the constellation Ursa Major – the Great Bear.

Diana and Callisto is one of six large mythological paintings that Titian produced between 1549 and 1562 for Prince Philip, King of Spain from 1556, all of which have subjects drawn from the Metamorphoses. Titian coined the term ‘poesie’ (poems) for his compositions because he regarded them as the visual equivalents of poetry. This comparison recalls the paragone, a debate among artists and theorists in Renaissance Italy about the rival claims made for the arts. The Roman author Plutarch’s observation that ‘Painting is silent poetry, and poetry is painting that speaks’ was frequently cited in favour of painting.

Diana and Callisto was delivered to Philip along with Diana and Actaeon in 1559. We know that the pictures were designed to be displayed together as a stream flows from one to the other, creating a rhythm across the two canvases. However, the light as depicted falls from opposite sides – from the left in Diana and Actaeon and the right in Diana and Callisto. This indicates that Titian had a placement between two windows in mind, even if only in the abstract – Philip was moving around at the time, and it is highly unlikely that he had a specific destination for the pictures. In any case, the two paintings have remained together throughout their history. Around the time he was working on the pair, Titian began another painting associated with them, The Death of Actaeon. For some reason, Titian never sent this painting to the King and it remained in his studio unfinished at his death.

Probably in the mid-1560s, some years after the dispatch of Diana and Callisto to Spain, Titian and his workshop produced a full-sized variant of it (Kunsthistorisches Museum, Vienna). It was common at the time for artists to make copies and variants of successful compositions for other patrons.

For many years, Diana and Actaeon and Diana and Callisto were on loan to the Scottish National Gallery from the Duke of Sutherland’s collection. In 2009 and 2012 they were bought for the nation jointly by the National Gallery and National Galleries of Scotland. They are now displayed at both the National Gallery and the Scottish National Gallery, changing location between London and Edinburgh at intervals of a number of years.