García de Avellaneda y Haro

His relationship with the Count Duke of Olivares helped him to occupy important positions in the service of Philip IV and Mariana of Austria: he was a knight of the Order of Calatrava, President of the Council of the Indies (1632–1665) and simultaneously President of the Council of Finance (1643–1645).

During his viceroyalty he had to face a French attack carried out by Henri II, Duke of Guise during the Franco-Spanish War and the plague of 1656.

[2][3] After his return to Spain, he was Mayordomo mayor of the King (1658–1660) and president of the Council of Castile (1658–1668).

After the death of Philip IV in 1665, he continued to play a significant role, since it was the Count of Castrillo who actually signed the royal will due to the physical inability of the Monarch.

He was also one of the seven witnesses of the aforementioned will, and in the clauses of the same, his appointment to two fundamental positions is found : that of member of the Council of Guardians, provided for in the event of the death of the King with minor children, as would finally occur, and that of member of the Governing Board of the royal minority, in which he intervened as President of the Council of Castile, who was considered the most important public figure after the Monarch.