New regime

Upon the ascent of Charles IX, Crussol was elevated to the Order of Saint Michael and granted a place on the conseil privé.^[8] At the regional Languedoc estates that proceeded the estates general in March 1561, a Huguenot delegate called for the confiscation of all clerical property and using the proceeds from selling it to maintain a reformed clergy. Crussol was among those nobles who supported this proposal alongside much of the rest of the nobility of Languedoc. In August at Pontoise a modified version of this proposal was endorsed by the general second and third estates.^[9]

Commissioner

With word reaching the court of the violent disorder in Provence Crussol was dispatched as a commissioner to work with the governor Tende in suppressing the local civil war that was developing between Catholic militants under Carcès and Protestant under Montbrun.^[10] The municipal consuls of Aix protested Crussol's selection as commissioner, arguing his Protestantism made him too biased to conduct the role, in response to this the more militant Catholics were ejected from the consulate of Aix and several nearby towns on royal orders. However his preference for Protestant allies in the province would manifest in the following months.^[11]

Reporting from the estates of Provence in April 1561 Crussol emphasised the great obedience and respect for the king his co-religionists held in Provence.^[12] In the same year Catherine oversaw his appointment as 'lieutenant and commander' of Languedoc. He quickly took advantage to assert his authority over the regions of the governorship where his estates were located in the east.^[13] Throughout the 1560s Crussol would outbid other buyers to snap up alienated church land when it became available in the diocese of Uzès, consolidating his holdings in the region.^[14]

First civil war

During the first civil war Crussol was tasked with pacifying Languedoc, however he seemed more interested in carving out a principality for himself.^[15] The Languedoc estates of November 1562 and March 1563 concerned themselves with building and financing a military defence system to be put under the command of Crussol.^[16] The estates of November met on Crussol's estates, arriving from Nîmes and after their deliberations he agreed to become the governor of Languedoc for the Protestant cause.^[17] He promised them he would tolerate no Catholics in his following and the estates gave him 400,000 livres. He proceeded to appoint subordinate governors to administer the province with the assistance of a small council. His brother Beaudiné was made lieutenant-general of Languedoc. Towns were compelled to sign oaths, on a similar line to the oaths Catholic Leagues extracted.^[17] With Condé captured on the field at the Battle of Dreux in December 1562, Catherine took the opportunity to chastise Crussol, urging him to 'remember his duties as the kings subject, and to get his fellow Protestants to disarm.^[18]

Edict of Amboise

In 1563 with peace declared in the Edict of Amboise, Provence successfully secured an exemption from the edicts terms. Marseille campaigned successfully against Crussol's provisions, arguing Protestantism had never been practiced in the city, so its introduction would be improper.^[19] Catherine protested the fact Crussol remained under arms, urging him to hand his troops over to Guillaume de Joyeuse.^[20] Crussol, who despised Joyeuse, abstained from handing over the territories under his control until August 1563.^[21] Crussol and his brother d'Acier protested as Damville the new governor of Languedoc began installing Catholic town councils in dozens of Protestant towns in the governorship. The central government sent two commissioners down to ensure elections for towns complied with the Edict of Amboise.^[22]

Royal tour

During the royal grand tour of 1564 the king, his mother and many notables spent time at Crussol's residence on their journey, before he accompanied them on in their journey to Nîmes.^[23] When the king reached Montpellier, he held council to discuss religious matters, among those sitting on the council was Crussol.^[24] In May 1565, while the king held a lit de justice in Toulouse, he elevated Crussol to the duc d'Uzes , though on the condition that if there was no male heir the duchy would pass to the crown.^[25]

Loyalist

Crussol rarely visited his holdings in the following years, consumed as he was in efforts at court, and with restoring Catholic worship in Nîmes. In 1566 he wrote to the king of his success in reinstalling the bishop of the city. In January 1571, the duchy of Uzès was further elevated into a peerage of the realm.^[26]

With the shockwaves that rippled out from the Massacre of Saint Bartholomew he converted to Catholicism.^[27] In the wake of the massacre, La Rochelle entered rebellion against the crown. Crussol aided the crown in their efforts to subdue the city, however, in the poor conditions of the siege lines he developed an illness, and he died on 11 August 1573. Having no children, he was succeeded to his titles by his brother d'Acier.^[28]