The sitter in this portrait and the artist who painted her have not been firmly identified. Painted in a formal style traditional of Spanish court portraiture in the sixteenth century, the painting may possibly represent the younger daughter of Philip II of Spain and his third wife, Isabel de Valois, the Infanta Catalina Michaela.

In the last two centuries the painting has been attributed to Spanish court portraitist Anthonis Mor (c. 1518-1576) and later to his pupil and successor under Phillip II, Alonso Sánchez Coello (1531-1588). Until recently it was thought to depict Isabel de Valois, Queen of Spain (1545-1568). Several portraits of Isabel de Valois now in the Museo del Prado, Madrid, show the Spanish Queen wearing a dark dress decorated with gold and jewels and a high, lace ruff similar to that in the Royal Collection painting. These similarities may have contributed to the previous identification of the sitter as Isabel de Valois.

However, this style of dress is consistent with the popular fashions of the Spanish court in the second half of the sixteenth century, making identification of any one sitter more difficult. Similar fashions can also be seen in known portraits, also in the Museo del Prado, of Infantas Catalina Micaela and Isabella Clara Eugenia, the daughters of Isabel de Valois.

This portrait has often been associated with another in the Royal Collection (RCIN 402954) and the sitters are traditionally thought to be sisters. It is plausible that the paintings represent Infantas Catalina Micaela and Isabella Clara Eugenia respectively. The comparison of the two Royal Collection portraits with known portraits of the Infantas has led to this tentative identification.

Stylistically, the painting follows the traditionally manner of Spanish court portraiture of the sixteenth century. Whoever the artist was, they were more concerned with the portrayal of the sitter's status than with reproducing an individual likeness. Portraits of Spanish Habsburg Queens and Princesses were designed to be complementary to those of Kings and Princes and have a distinct iconography. Sitters were depicted in formal attitudes without humor or seductive charm. Spanish court portraiture of this period was also characterized by a precise attention to the elaborate textures and details of the ornate attire worn by the court, as seen in this painting.