Infantin Anna (1601-1666), Königin von Frankreich, Bildnis in ganzer Figur im Alter von neun Monaten

This extraordinary portrait, dated 1602 and held at the Kunsthistorisches Museum, shows the Infanta Anna at nine months of age — making it one of the earliest known portraits of any individual in the Spanish Habsburg series. The fact that such a young infant was formally painted reflects the intensity of dynastic record-keeping in the Habsburg system: even a baby of nine months was a political entity whose image needed to be documented and distributed. Anna (1601–1666) would eventually become Queen of France as wife of Louis XIII and mother of Louis XIV — her historical significance in retrospect lends these early images a retrospective poignancy. Pantoja faces an almost impossible task: a nine-month-old cannot pose, cannot maintain stillness, and has no social persona to project. His response was to emphasise the extraordinary costume — a miniature adult court dress of extraordinary elaborateness — and to catch the infant's face with as much specificity as the circumstances allowed.

The technical challenge of portraying an infant nine months old required Pantoja to work quickly and rely heavily on the costume as the painting's anchor. The baby's face is rendered softly, the features' roundness and lack of definition conveying genuine infant physiology rather than adult idealisation. The elaborate dress, by contrast, is treated with the same precise attention Pantoja brought to adult royal costumes, creating a striking contrast between tiny person and monumental clothing.