Alonso Sánchez Coello was one of the foremost portraitists of the later sixteenth century and a pioneer of the Spanish tradition of portraiture. A follower of Titian, he combined the golden tones and use of light found in Venetian painting with a precision of representation learned in the studio of his Flemish Master, Anthonis Mor. Mor was court painter to Phillip II of Spain but returned to the Netherlands in 1561, after which Coello took his former master's place. Coello remained at the Spanish court in Madrid until his death in 1588 and continued to enrich the style inherited from both Titian and Mor, bringing a distinctive use of colour, sharpness of execution and heightened realism to Spanish painting.

This painting depicts fifteen-year-old Archduke Ernest of Austria as the mirror image of his brother Rudolf, the future Holy Roman Emperor, of whom Coello painted a portrait the year before (RCIN 405798). Ernest and Rudolf resided in the Spanish court of their uncle King Philip II for more than eight years (1563–1571), and it is likely that Philip commissioned these portrait of his nephews.

The direct gaze and dignified, formal pose of the sitter are characteristic of Spanish court portraiture. Coello portrays the teenage prince as a confident young man, complete with hereditary 'Habsburg chin' emphasised by a high stiff ruff. Like his brother, Ernest wears Spanish-style dress, including wams (doublet) and light-coloured bell-shaped trousers with distinct codpiece.