In prerevolutionary France, the primary role of the three estates was to periodically convene to consult the king on matters of the state, particularly those matters perceived as controversial. Initially, the king required this consultation much more than he would in later years. The king would eventually dispense with much of this need for consent on matters of law. The other general function of the three states was, when convened into the States General, to enforce the fundamental laws of the realm, customary laws even the king could not supersede. The States General alone could enforce them. Perhaps the most important of these laws concerned the succession of French rulers, particularly at points when the line of succession is broken. In those cases, it was left to the States General to select the new ruler. As a collective unit, the three estates exercised a sizeable amount of influence on French politics.
Considered individually, the three estates also served other functions which derived from their membership in those estates. The clergy in the first estate, all of whom were Catholic and most of whom held high religious offices, were responsible for maintaining the strength of Catholicism in France. The nobility of the second estate formed the leadership in France, occupying the higher, more influential offices in government. The third estate, though it far outnumbered the other two estates, exercised far less power. They were responsible for paying the vast majority of the taxes, and they held virtually all of the occupations, thus ensuring the functioning of society.