[6] In January 1442, aged 22, he had reached the office of chamberlain of the prince, the highest position in the house of the heir after the steward, a dignity still in the hands of the constable Álvaro de Luna.
[citation needed] Other titles earned by Pacheco would include Adelantado of Castile from 1451 to 1456, and of Merino Mayor of Asturias from 1461 to 1462.
He was also made Master of the Order of Santiago in 1467 by Prince Alfonso,[9] who had been proclaimed king by some Castilian nobles in the Farce of Ávila.
The Aragonese king's reaction was to win the friendship of Castile and void the Castilian-French alliance, promising his son Fernando to Pacheco's daughter, Beatriz.
[9] In 1469, Princess Isabella, half-sister of Henry IV, married Ferdinand of Aragón,[11] against the will of the king and overriding prior diplomatic agreements, starting thus the War of the Castilian Succession,[12] in which Pacheco supported Princess Juana, Henry IV's daughter.
[13] Pacheco died on 4 October 1474, in Santa Cruz, near Trujillo, shortly before the death of King Henry IV, of a throat ailment.
They were legitimized on 25 April 1456, by King Henry IV of Castile:[17] By an unknown woman, he fathered Alonso, Rodrigo, Beatriz, and Leonor.