The government spent more than they had, in debt from war, food prices were high in 1789. The government was under the rule of feudalism.
The third estate paid taxes and lived a tight and unequal life as the king and queen, who were using all the money and lived a comfortable life
Declaration of the Rights of Man
The court which was controlled by nobles says that each estate would meet and vote separately so their votes could outnumber the Third Estate. But the Third Estate refuse and walk out to a tennis court and name themselves the National Assembly
Death of the King
The National Assembly hoped that the king would go alone with them, but the king was on the side of the nobles. 18,000 soldiers were called to Versailles. On July 14, war broke out Bastille, a fortress and prison in Paris. The governor and other officials were killed.
The National Assembly was in control of the government by summer, it brought an end to feudalism. Later, the National Assembly passed the Declaration of the Rights of Man. It stated "liberty, equality, fraternity", ended the power of the nobles.
While the National Assembly took control, many nobles left France and the King was caught trying to flee. He was beheaded in front of many people, considered a traitor of the country.