 In 1991 Christiaan Schuckman discovered a set of signed plates in Madrid that can be attributed to the engraver of the First Folio portrait . These plates bear Droeshout 's signature and are stylistically similar to his portrait of Shakespeare . ( They include a portrait of the priest and writer Franciso de la Peña that has a striking resemblance to the English poet ) . On the evidence of these plates , which were made between 1635 and 1639 , Schuckman attributed the portrait of Shakespeare to the younger Martin and suggested that the engraver had converted to Catholicism and emigrated to Spain in 1635 , where he continued to work . 
