The main causes of the French Revolution are:

Political and social inequalities
France was, at the time, an absolute monarchy, which has become more and more unpopular as a form of government. Under the king were the First Estate and the second Estate composed of the nobles and the clergy who had special privileges. The Third Estate is composed of the bourgeoisie, the peasants and the artisans. Even though the working class people constituted the majority of the French population, and that they paid heavy taxes, they didn’t have power and freedom in politics. Thus, the peasants and the growing bourgeoisie were very resentful towards these groups that benefit from many privileges.

Unfair taxation
Kings increase taxation in hope to improve the financial situation. However, there is an unequal collection of France’s consumption taxes. Also, clergy and nobles are excluded from paying taxes.

Debt
France was deeply indebted, because of Louis XIV’s heavy expenditures, (including Versailles) and because of France’s involvement in the Seven Years War and the American War of Independence. Louis XIV’s successors tried to improve the financial situation by borrowing money, and by selling noble titles, but the problem is that those who bought noble titles didn’t need to (exempted) to pay taxes anymore, which leaves the financial problem unsolved.

American influence and Enlightenment theory
Since France sent its navy and troops to aid the rebelling colonists,