It should not be confused with the role and title of a "Conseil du Roi", a type of public prosecutor in the French legal system at the same period.
Under Charles V, it was put forward that the king made decisions only after "good and careful deliberation" (French: bonne et mûre délibération), and this principle was maintained by his successors; the closing formula of royal acts "le roi en son conseil" expressed this deliberative aspect.
Even during the period of French absolutism, the expression "car tel est notre bon plaisir" ("as such is our pleasure") applied to royal decisions made with consultation.
The council's purview concerned all matters pertaining to government and royal administration, both in times of war and of peace.
In addition to the King's Council, the consultative governing of the country also depended on other intermittent and permanent institutions, such as the States General, the Parlements (local appellate courts) and the Provincial Estates.
Over the centuries, the number of jurists (or "légistes"), generally educated by the université de Paris, steadily increased as the technical aspects of the matters studied in the council mandated specialized counsellers.
These counsellors, called conseillers d'État from the reign of Henry III on, were aided in their tasks by the maître des requêtes.
Under Charles VIII and Louis XII the king's council was dominated by members of twenty or so noble or rich families.
Under Francis I the total number of councillors increased to roughly 70 individuals (the old nobility was proportionally more important than in the previous century).
Francis I was sometimes criticized for relying too heavily on a small number of advisors, while Henry II, Catherine de' Medici and their sons found themselves frequently unable to negotiate between the opposing Guise and Montmorency families in their council.
In periods of crisis, the number of members of the Council tended to increase: 100 councillors under Charles IX, during the worst moments of the Wars of Religion.
From 1661 to the French Revolution, royal administration was divided between the various sections of the King's Council (roughly 130 people) and a small group of ministers and secretaries of state.
An ordinance by Charles VIII in 1497, and reaffirmed by Louis XII in 1498, removed this body from the king's council and established it as an autonomous court with the institutional name Grand Conseil.
Francis I created a Conseil des Affaires – a small informal group reuniting the chancellor, a secretary of commandments and several other close confidants – to deal with political and diplomatic issues, including war.
The Privy Council acted as a supreme court, pronouncing judgements on the various sovereign courts of the realm (including the parlements and the Grand Conseil), and provided final judicial review and interpretation of law (the request for which was called "évocation"), oversight of the judicial corps, and judged disputes on royal offices, church benefices and problems between Catholics and Protestants.
Even when the king was not in fact present as his councils, there were still considered to be presided over by him, and only the closing formula of their decisions changed: the expression "le Roi en son Conseil" was used when the king was not present at the meeting, the expression "le Roi étant en son Conseil" when he was.
In addition to the above administrative institutions, the king was also surrounded by an extensive personal and court retinue (royal family, valets, guards, honorific officers), regrouped under the name "Maison du Roi".
At the death of Louis XIV, the Regent Philippe II, Duke of Orléans abandoned several of the above administrative structures, most notably the Secretaries of State, which were replaced by councils.
These councils met in the King's Apartment, in a room called the "Cabinet du Conseil" (present in all royal residences).
Louis XV followed the same general rules but frequently interrupted discussion when it seemed to be going in a direction he disagreed with, rather than choose to go against the final opinion of the council.
The "Conseil des Dépêches" ("Council of Messages") oversaw the notices and administrative reports from the provinces sent by the governors and intendants, and thus dealt with domestic affairs coming under the purview of all four Secretaries of State.
Under Louis XIV, the schedule was slowed down, as the king had gotten into the habit of discussing these matters with his one-on-one meetings with his ministers; decisions taken were presented as "arrêts en commandement" even if they had not been officially deliberated in council.
The council met every Saturday, and sometimes on Friday, but also came together for additional meetings, some for several days in a row, as was the case during the Fronde parlementaire under Louis XV.
The "Conseil de Conscience" was created in 1720 by the Regent Philippe II, Duke of Orléans to oversee implementation of the clauses of the papal bull Unigenitus.
The Council of Finances' purview was large; it dealt with the royal budget, taxation, industry, commerce, money, contracts to the Farmers General, etc.
Like the "Grand Conseil", the Privy Council acted as a supreme court, pronounced judgements on the various sovereign courts of the realm (including the parlements and the "Grand Conseil"), and provided final judicial review and interpretation of law (the process of so-called "évocation), oversight of the judicial corps, and judged disputes on royal offices, church benefices and problems between Catholics and Protestants.
The council was the largest of the royal councils, and was composed of the chancellor, princes of the royal bloodline ("princes du sang"), dukes with peerage ("ducs et pairs"), the ministers and secretaries of state, the contrôleur général des finances, the 30 councillors of state, the 80 maître des requêtes and the intendants of finance.
The Privy Council met on Mondays in a special room, the "salle du Conseil" which was outside the King's apartment.
Before coming before a judicial session, affairs were submitted to the council by a maître des requêtes and studied by a group of state counsellors.
Under Henry IV and Louis XIII the administrative apparatus of the court and its councils was expanded and the proportion of the "noblesse de robe" increased, culminating in the following positions during the 17th century: Royal administration in the provinces had been the role of the bailliages and sénéchaussées in the Middle Ages, but this declined in the early modern period, and by the end of the 18th century, the bailliages served only a judicial function.