He was an excellent pupil, at the age of 14 being able to translate the works of Livy and Quintus Curtius with ease, but he was inspired by his father's example and wanted to go to sea.

In 1625 he contracted with the Crown to construct two vessels, which were completed promptly after the victory of Dutch Admiral Piet Pieterszoon Hein in Cuban waters.

Díaz Pimienta was appointed superintendent of the shipbuilding factories in the port of San Cristóbal de la Habana.

[1] In 1638 Pimienta was vice-admiral in a Spanish-Portuguese fleet commanded by the Count of Torre, Dom Fernando de Mascarenhas, directed against the Dutch base at Pernambuco in Brazil.

After arriving with his weakened force at Salvador da Bahia, Mascarenhas delayed for about a year before sailing on Pernambuco with the intent of landing troops to take the town.

Shortly after the first revolutionary explosion in Lisbon, the fleet of galleons commanded by General Diaz Pimienta arrived in Cartagena.

[6] Díaz Pimienta sailed from Cartagena to Providence Island with seven large ships, four pinnaces, 1,400 soldiers and 600 seamen, arriving on 19 May 1641.

[8] At first Díaz Pimienta planned to attack the poorly defended east side, and the English rushed there to improvise defenses.

With the winds against him, Díaz Pimienta changed plans and made for the main New Westminster harbor and launched his attack at dawn on 24 May.

[11] The Spanish found gold, indigo and cochineal as well as the slaves, worth a total of 500,000 ducats, some of the accumulated booty from the English raids.

[12] Rather than destroy the defenses, as instructed, Díaz Pimienta left a small garrison of 150 men to hold the island and prevent occupation by the Dutch.

Diaz ordered the mutineers to be tried in a court chaired by General Rodrigo Lobo, with the Portuguese Juan Rodriguez de Vasconcellos Sousa, Count of Castelo Melhor, as a prosecutor.

[6] Before the sentence was carried out, Castilmillor and two of his companions escaped from prison and managed to board a Portuguese ship that the Duke of Braganze had sent from Lisbon.

[19] On 14 April 1648, while Spain was at war with France over the territory of Roussillon, the king appointed Díaz Pimienta Governor of Menorca, Royal Councillor and Captain General of the Ocean Sea Fleet.