Overview
Jacob the Dacian (Spanish: Jacobo Daciano; Latin: Iacobus de Dacia; c. 1484 – 1566) was a Danish-born Franciscan friar. He achieved fluency in eight languages and fame among the indigenous people of Michoacán as a righteous and helpful man toward his flock. His relics, now lost, were kept for a long time by the indigenous people of Tarécuato (in Tangamandapio) who still celebrate his birthday every year. Jacob has been identified as a son of King John of Denmark.
Name
The translation of his name into Medieval Latin as Iacobus de Dacia stems from the fact that, during the Middle Ages in Scandinavian affairs, the Latin toponym Dacia stood for Denmark-Sweden.
Brother Jacob also went by the name Iacobus Gottorpius, referring to the royal estate of Gottorp (now located in Germany), and also signed as Jacobus Danus "Jacob the Dane".
Royal descent
Danish historian Jørgen Nybo Rasmussen (Rasmussen 1974, 1986) has asserted that Jacob was a son (possibly extramarital) of King John of the Kalmar Union and a younger brother of King Christian II, both Danes. This has not been mentioned by all historians but is also the basis for a novel Brother Jacob by Danish author Henrik Stangerup. Key arguments in a case for Jacob's royal lineage are the facts that he described himself as coming from Gottorp, the estate of Kings Christian I and John of Denmark; that he had an excellent education normally reserved for the higher nobility; and that he seemed to enjoy the protection of higher political forces. It was also common for younger sons of royalty to enter into the clergy, since they normally would not inherit the thrones. Jacob's position as an inter-continental missionary would have been very unusual for a royal prince.
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