On 13 May 1796, a royal decree issued by Queen Maria I of Portugal, upgraded the title of Count of Miranda do Corvo to Duke of Miranda do Corvo (in Portuguese Duque de Miranda do Corvo), who should be beard by the Duke of Lafões heir during his father's life.
List of counts of Miranda do Corvo (1611) and Marquesses of Arronches (1674)
Henrique de Sousa Tavares (c.1550– ? ), 1st Count of Miranda do Corvo;
Diego Lopes de Sousa (c.1595–1640), 2nd Count of Miranda do Corvo;[1]
Henrique de Sousa Tavares (1626–1706), 3rd Count of Miranda do Corvo and 1st Marquis of Arronches;
Diogo Lopes de Sousa (1646–1672), 4th Count of Miranda do Corvo (died before his father and that is why he was not Marquis of Arronches);
Mariana Luisa Francisca de Sousa Tavares Mascarenhas e Silva (1672–1743), 5th Countess of Miranda do Corvo and 2nd Marchioness of Arronches;
Luisa Casimira de Sousa Nassau e Ligne (1694–1729), 6th Countess of Miranda do Corvo;
Pedro Henrique de Bragança (1718–1761), 7th Count of Miranda do Corvo, 3rd Marquis of Arronches and 1st Duke of Lafões.
(for the following Counts/Marquesses see Duke of Lafões)