Manuel I of Portugal
Manuel's mother was the granddaughter of King John I of Portugal, whereas his father was the second surviving son of King Edward of Portugal and the younger brother of King Afonso V of Portugal. In 1495, Manuel succeeded his first cousin, King John II of Portugal, who was also his brother-in-law, as husband to Manuel's sister, Eleanor of Viseu.
Manuel I of Portugal
Manuel grew up amidst conspiracies of the Portuguese upper nobility against King John II. He was aware of many people being killed and exiled. His older brother Diogo, Duke of Viseu, was stabbed to death in 1484 by the king himself.