The adolescent King Sebastian is depicted with all of the customary conventions associated with formal portraits of the Habsburgs. These portraits´ models of authority and power, which perfectly embody the identification of the model and the representation of the monarchy as defender of Christianity, were codified by Titian and Mor in images of Charles V and Philip II. Mor´s stay in Portugal in 1552, where he worked for Marie of Hungary and Catharine of Austria, was decisive for the development of a school of portraiture that came to Spain via Portugal when Juana de Austria returned to Valladolid accompanied by her painter, Sánchez Coello.

This painting´s similarity to the only signed and dated portrait of King Sebastian, which is in the Monastery of the Descalzas Reales, has led it to be attributed to Cristóbal de Morales, who was known for his portraits of that Portuguese king. His work shows how portraiture in the Portuguese court had adopted Sánchez Coellos´s models without abandoning some aspect of Northern painting as well as the idealization and taste for Italian mannerism the are part of a tradition established in Portugal by Fracisco de Holanda (Text drawn from Ara, J.: El Linaje del Emperador, 2000, p. 300).