Before 1789, France was ruled by the nobles and the Catholic Church. The ideas of the Enlightenment were beginning to make the ordinary people want more power. They could see that the American Revolution had created a country in which the people had power, instead of a king. The government before the revolution was called the "Ancient (old) Regime".
The high price of bread and low wages given to workers caused the ordinary people to suffer from hunger and malnutrition. This made them dislike the rich nobles, who had the money to eat well and build huge houses.
The first and the second estate i.e., the Clergy and the Nobility, enjoyed all the privileges and rights but the third estate (middle class,city workers and peasants) had to pay tithes and taille (taxes paid to Church and the court).