Francisco Gómez de Sandoval y Rojas, 1st Duke of Lerma, 5th Marquess of Denia, 1st Count of Ampudia (1552/1553 – 17 May 1625), was a favourite of Philip III of Spain, the first of the validos ('most worthy') through whom the later Habsburg monarchs ruled.

His administration was marked by costly wars, including the Twelve Years' Truce with the Dutch Republic, financial mismanagement, and the controversial expulsion of the Moriscos.

[4] Others however, claim that Lerma was a fully capable favourite, as he led Castile and the Habsburg dominions on a more modest and economically viable course of peace than both Phillip II and Olivares during the reign of Philip IV – both figures that have received far more positive recognition by historians.

According to Friar Juan Fernández de Medrano in 1601, Lerma was viewed by his contemporaries as the singular soul and guiding force of the Spanish monarchy, a leader whose virtues illuminated the kingdom like the Sun governing the heavens.

Philip III, preoccupied with piety and indolence, soon created him Duke of Lerma (1599), pressured the papacy to make his uncle Bernardo a Cardinal and delegated to him governorship of certain public offices and management responsibility of particular lands, authorized by the King and Queen, of the Kingdoms of Castile and Aragon.

Lerma's financial horizons remained medieval: his only resources as a finance minister were the debasing of the coinage and edicts against luxury and the making of silver plate.

It is probable that he would never have lost the confidence of Philip III, who divided his life between festivals and prayers, if not for the domestic treachery of his son, who allied himself with the King's confessor, Luis de Aliaga Martínez, whom Lerma had introduced.

[4] As a protection, and as a means of retaining some measure of power in case he fell from favour, he had persuaded Pope Paul V to create him cardinal, the previous March (1618).

He was ordered by the count of Olivares to reside in Tordesillas but he did not obey and appealed to Pope Gregory XV and the College of Cardinals defended him, considering his banishment an attempt against ecclesiastical freedom and the prestige of the cardinalate.

Lerma was also responsible for the appointment of Don Pedro Franqueza to reform royal finances, but who instead managed to embezzle enough funds to purchase the title of Count of Villalonga.

[4] On the hilltop overlooking the village of Lerma in Old Castile that provided his grand title, the duke built a palace (1606–1617, by Francisco de Mora) capped with corner towers, on the site of a fortification, ranged round a double-arcaded courtyard facing an arcaded square and linked to the rebuilt church of San Pedro with a private passageway.