The fundamental laws of the Kingdom of France were a set of unwritten principles which dealt with determining the question of royal succession, and placed limits on the otherwise absolute power of the king from the Middle Ages until the French Revolution in 1789. They were based on customary usage and religious beliefs about the roles of God, monarch, and subjects.
Although discussion of the concepts surrounding the idea of fundamental laws which organize the body politic go back to the earliest period of the French monarchy, the expression "fundamental laws" (lois fondamentales) itself didn't come into use until the second half of the 16th century, even though the theories underlying it were fully mature by that point.
The Parliament of Paris as late as 1788 listed a number of rights that it considered fundamental, including that of the ruling house to the throne of France, but also those of the ordinary citizen to never be brought for any matter before judges other than those designated by law, and never to be arrested without being brought before a competent legal authority.
Further information: Salic law
Early writers in the 9th to the 16th century, such as Smaragdus of Saint-Mihiel, Jonas of Orléans and Hincmar of Reims, saw the king as the embodiment of divine justice, from which he drew his authority.
Salic law was the ancient Frankish civil law code compiled around 500 AD by the first Frankish King, Clovis. Roman Law was written with the assistance of Gallo-Romans to reflect the Salic legal tradition and Christianity, while containing much from the Roman tradition. The text lists various crimes and the fines associated with them. It remained the basis of Frankish law throughout the early Medieval period, and influenced future European legal systems.
The best known tenet of Salic law was the exclusion of women from inheriting thrones, fiefs, or other property. The Salic laws were arbitrated by a committee appointed and empowered by the King of the Franks. Dozens of manuscripts dating from the sixth to eighth centuries and three emendations as late as the ninth century have survived. Its use of agnatic succession governed royal succession in the kingdoms of France and Italy.
The absolute monarchy in the kingdom was not the same as totalitarian dictatorship, and there were limits on the king's power. These arose chiefly from religious constraints: because the monarchy was considered to be established by divine right, that is, that the king was chosen by God to carry out his will, this implied that the king's subjects should obey and respect him. The king is accountable only to God, however he doesn't have despotic power. There are limits imposed by the Gospels, and the king does not have the right of life and death over his subjects, and has a duty to be virtuous.
While ancient France did not have a constitution in the formal sense (written document containing constitutional rules), it had already developed a constitution in the material sense (organization of power) in the Middle Ages.
The fundamental laws can be grouped into four key themes:
In addition, there was also:
Towards the end of the Middle Ages, the monarchy was evolving in the direction of absolutism, placing the king above the law, according to the political ideas of Jean Bodin and his "Six Books of the Republic" of 1576. This implied that with regard to governmental powers, the king makes the laws, the king executes the laws through his ministers and officers, and the king delegates his judiciary power to independent magistrates who handle appeals; nevertheless, the king retains the right to detain anyone of his choice by a lettre de cachet.
Despite this evolution and Bodin's theories, the power of the king remained strictly controlled by traditional institutions, like parliaments, and provincial, parish, and clergy groups, and local customs. Thus, for example, when Louis XIV revoked the Edict of Nantes in 1685, he was acting in response to his entourage, his court, and influential men in the kingdom. The absolute monarchy came to an end in 1789 with the French Revolution.