She drew popular support for the cause and oversaw the reinforcement of the city's defences, ultimately resulting in negotiations ending with the royalists granting Toledo generous concessions.

[2] Taught by Hernán Núñez and Peter Martyr d'Anghiera, she was educated in the Latin and Greek languages, as well as mathematics, history, poetry and Christian scripture.

[11] When López de Padilla finally arrived in Granada on 14 August 1511, Pacheco had not yet met her betrothed[12] and was apparently apprehensive about the arranged marriage.

[15] In 1514, they began making preparations for the wedding; the expenses of the event weighed heavily on Mendoza, who increasingly resented Fernando for his lack of support.

[16] He continued to request that Fernando help finance the event, but was repeatedly rebuffed, causing him great anxiety and financial stress, as he was forced to sell his jewellery and go into debt to "everyone in the city" in order to pay for the wedding.

She also kept her father informed of his enemies' activities at King Fernando's court, and acted as an intermediary between the Mendozas and Padillas, placing her at the centre of the two families' plans and aspirations.

[24] Juan de Padilla defended the rites of the hidalgos (petty nobility) and the urban poor against the monarchy and the barons, gaining him substantial support in Toledo, where he led the Revolt of the Comuneros against the Crown.

[25] In January 1521, after the death of the Flemish William de Croÿ, the Archbishop of Toledo, Pacheco seized the opportunity to promote a member of her own family to the position.

[23] She actively campaigned for the election of her brother Francisco de Mendoza [es],[27] attempting to garner support before Carlos I was able to act against her.

[23] But a different faction of the comuneros opposed her moves and invited Antonio Osorio de Acuña, the Bishop of Zamora, to contest the election and limit Pacheco's power in Toledo.

[26] Although she feared Acuña's arrival would challenge her "uncontested authority",[28] the Bishop offered an exchange, in which she would support his election bid in return for her husband being appointed as commander of the Order of Santiago.

[28] After the defeat of the comuneros at the Battle of Villalar in April 1521, Pacheco's husband Juan de Padilla was executed by the royalist forces.

[32] Pacheco herself adhered to her family's legacy of resistance to foreign monarchs and maintained an intransigent commitment to the comunero cause, the latter of which saw her dubbed "La Valerosa" (English: The Courageous) by the historian Prudencio de Sandoval.

Despite the tide of the conflict changing in favour of the royalists, Pacheco managed to rally Toledo into maintaining its resistance, even after the rest of Castile was pacified.

[34] Pacheco secured advantageous terms for Toledo's surrender,[35] including the return of the Padillas' sequestered property and a royal allowance, the latter of which was petitioned for by her brother Luis.

In Toledo, the comuneros headquarters were demolished, a monument condemning Pacheco's revolt was raised in the city centre, and salt was ploughed into the earth,[38] preventing plants from growing in the Plaza de Padilla up into the 21st century.

[42] She was strongly disliked by contemporary chroniclers, due to her transgressions of traditional gender roles by taking up political and military command.