The Brazilian monarchy came to an end on November 15, 1889, following a military coup which overthrew Emperor Dom Pedro II and established a republic. According to the Imperial Constitution (1824), the Brazilian monarchy was hereditary according to male-preference primogeniture among the dynastic descendants of Emperor Pedro I of Brazil, and the crown could only be inherited by one who held Brazilian nationality. The Imperial constitution also states that the Emperor and his heir presumptive should be Catholic, and the marriage of the princess heir presumptive required consent of the Emperor or the Assembly.
Claimants to headship of the post-monarchic Brazilian Imperial legacy descend from Emperor Pedro II, including the senior agnates of two branches of the House of Orléans-Braganza; the so-called Petrópolis and Vassouras lines.Prince Pedro Carlos of Orléans-Braganza (born 1945) heads the Petrópolis line, while the Vassouras branch is led by his second cousin, Prince Luiz of Orléans-Braganza. Rivalry within the family erupted in 1946 when Dom Pedro Gastão (1913–2007) repudiated the renunciation to the throne of his late father, Pedro de Alcântara, Prince of Grão-Pará (1875–1940), for himself and his future descendants, when he made a non-dynastic marriage in 1908. Pedro de Alcântara was the eldest son of the Princess Imperial Isabel (1846–1921) who, as Pedro II's elder daughter and heir presumptive when he was dethroned, became the last undisputed head of the family after her father's death in exile in 1891. Pedro Carlos is Dom Pedro Gastão's eldest son. Dom Luiz descends from Isabel's younger son, Prince Luís (1878–1920) who, by a Bourbon princess, fathered Prince Pedro Henrique (1909–1981). Dom Luiz is Pedro Henrique's son by a Bavarian princess and upholds his dynastic claim to the same legacy.