In Virgil's Aeneid, Iris, goddess of the rainbow that trails behind her faintly drawn in black chalk, comes to Turnus, leader of the Rutuli nation, as a messenger from Juno. Iris tells Turnus to attack Aeneas's invading army now, for Aeneas has left camp. Ultimately, however, Aeneas killed Turnus and founded a city, which became Rome. The black chalk study of a Roman helmet in the upper left probably relates to the verso sketch of groups of ancient Roman soldiers.
Pier Francesco Mola displayed his distinctive talent for incorporating figures into lush, windswept landscapes that enhance the scene's drama. He usually mixed pen and chalk as he did here, first quickly laying down the composition's essentials using black chalk, then picking out the most important lines in pen and ink. His characteristic fluid dark washes increase the sense of movement and tension.
Mola made this study for a fresco on the vault of a room in a prince's summer palace. After a dispute with the prince, Mola left the project unfinished and it was later destroyed.