Like his wife, D. Luis de Almeida was also descended from the 1st Count of Abrantes but by his second son, D. Diogo Fernandes de Almeida, 6th Prior of Crato. His father, D. António de Almeida, was the head of one of the branches of the important Almeida clan and in addition to his own assets inherited substantial estates from his mother, D. Maria de Portugal, descended from the Counts of Vimioso and the Counts of Castanheira. Luis acceded to his parents' prosperous estate together with his father's commandaries of São Martinho da Lordosa, Soalheira and Bemposta in the Order of Christ. In 1647 he was posted to Brazil as "Mestre de Campo" of one of the elite regiments of Royal Marines, where he served favourably during the War of Acclamation against Spain. He was later Governor General of Rio de Janeiro and, as a trusted courtier of the Queen Regent, D. Luisa de Gusmão, given the highly sensitive role of last Portuguese Governor General of Tangiers, with the responsibility of managing its transition to English rule in 1662, as part of the dowry of the Infanta Catarina on her betrothal to King Charles II. His experience as a soldier and administrator, as well as his position at Court, earned him the title of 1st Count of Avintes in 1664, during his final administrative posting as Governor General of the Kingdom of the Algarve, where he was stationed between 1663 and 1667 and where he also left his mark.