Don Teodósio, Prince of Brazil, Duke of Braganza (Teodósio de Bragança; ; 8 February 1634 – 15 May 1653) was the heir apparent son of John IV of Portugal (first king of the House of Braganza) and his wife Luisa de Guzmán. In 1645, he was given the title of Prince of Brazil, a new crown princely position thus created. Also, his father granted him the duchy as 10th Duke of Braganza, presumably after his uncle Duarte died in 1649. Biography He was born on 8 February 1634 in Vila Viçosa and was the heir to the throne of Portugal from 1641 until his death at only 19 years of age. When the prince was 13 years old, he took part in the State Council's reunions. Teodósio's death, on 15 May 1653, due to tuberculosis, caused great unrest in the kingdom. His next brother, the medically and mentally problem-ridden Afonso, succeeded him as Prince of Brazil, Duke of Braganza and heir apparent of the kingdom. Due to mental incapacity and impotence, Afonso would eventually be deposed by Peter II and died childless. Interests Teodósio was a gifted young man. He knew Greek and Latin, was keen on philosophy and well respected amongst the great intellectuals of the time. He had a great interest in astrology. He had a collection of charts of his family and made predictions on several political subjects. His astrological interests were encouraged and aided by his tutor, the Jesuit priest António Vieira. Under the tutelage of astrologers of the day, he composed many astrological charts. See also Prince of Brazil Afonso VI of Portugal Pedro II of Portugal Ancestry References External links Dom Theodosio the Astrologer Prince Genealogy of Prince Teodósio House of Braganza 1634 births People from Vila Viçosa 1653 deaths Teodosio 3 Princes of Brazil Portuguese Baroque composers Portuguese infantes Princes of Portugal 17th-century Portuguese people 17th-century astrologers Burials at the Monastery of São Vicente de Fora Heirs apparent who never acceded 17th-century classical composers Portuguese male classical composers 17th-century deaths from tuberculosis Tuberculosis deaths in Portugal Sons of kings