The dukes of Cadaval were a junior branch of the House of Braganza, an influential family that supplied Portugal with kings and emperors. In the second half of the 15th century, the second Duke of Braganza married well and acquired a large estate north of Lisbon known as Cadaval. His descendants grew even more wealthy and influential through new marriages and associations with the royal house of Spain. However, by 1640, the Portuguese nobles had enough of Spanish rule and rose in revolt. The success of their efforts brought the head of the House of Braganza onto the throne as King João IV. The new king wished to reward his most faithful followers. Among them was Francisco de Melo, Marquis of Ferreira, who encouraged João to claim the throne. To celebrate the birth of his second son (Dom Pedro), the king named Francisco de Melo’s son, Nuno Álvares Pereira de Melo, first Duke of Cadaval, in April 1648.