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.
Maria Pia de Saxe-Coburgo e Bragança
For at least several decades Maria Pia of Braganza had claimed to be the bastard daughter of King Carlos I, and even to be entitled to the style "Her Royal Highness" and the title "Infanta". It was not, however, until 1957 that she claimed to be the rightful queen of Portugal in succession to Manuel II, the son of Carlos I (and the purported half-brother of Maria Pia) who had died childless in 1932. 
On 15 July 1957 a group of ten Portuguese monarchists published a petition asking Maria Pia of Braganza to claim the throne. In 1958 she went to Portugal where she was received by the President Francisco Craveiro Lopes; the Prime Minister, António de Oliveira Salazar, however, refused to meet her. In the presidential elections that year Maria Pia of Braganza supported the failed candidacy of Humberto Delgado. She continued to support Delgado after he went into exile in Brazil.