Against a background of deepening economic crisis and general misery, exacerbated by the catastrophic harvest of 1788, controversy focused on how the Estates-General should be constituted. Should they meet separately as on the last occasion - in 1614? This was the solution favoured by the parlement of Paris, a measure of its reactionary nature: separate meetings would make it easy for the privileged, namely the clergy and nobility, to outvote the Third Estate , the bourgeoisie. The king ruled that they should hold a joint meeting, with the Third Estate represented by as many deputies as the other two Estates combined, but no decisions were made about the order of voting.

On June 17, 1789, the Third Estate seized the initiative and declared itself the National Assembly. Some of the lower clergy and liberal nobility joined them. Louis XVI appeared to accept the situation, and on July 9 the Assembly declared itself the National Constituent Assembly. However, the king then tried to intimidate it by calling in troops, which unleashed the anger of the people of Paris, the sans-culottes (literally, "without trousers").

On July 14 the sans-culottes stormed the fortress of the Bastille , symbol of the oppressive nature of the ancien régime . Similar insurrections occurred throughout the country, accompanied by widespread peasant attacks on landowners' châteaux and the destruction of records of debt and other symbols of their oppression. On the night of August 4, the Assembly abolished the feudal rights and privileges of the nobility - a momentous shift of gear in the Revolutionary process, although in reality it did little to alter the situation. Later that month they adopted the Declaration of the Rights of Man . In December church lands were nationalized, and the pope retaliated by declaring the Revolutionary principles impious.

Bourgeois elements in the Assembly tried to bring about a compromise with the nobility, with a view to establishing a constitutional monarchy, but these overtures were rebuffed. Émigré aristocrats were already working to bring about foreign invasion to overthrow the Revolution. In June 1791 the king was arrested trying to escape from Paris. The Assembly, following an initiative of the wealthier bourgeois Girondin faction, decided to go to war to protect the Revolution.

On August 10, 1792, the sans-culottes set up a revolutionary Commune in Paris and imprisoned the king. The Revolution was taking a radical turn. A new National Convention was elected and met on the day the ill-prepared Revolutionary armies finally halted the Prussian invasion at Valmy. A major rift swiftly developed between the Girondins and the Jacobins and sans-culottes over the abolition of the monarchy. The radicals carried the day. In January 1793, Louis XVI was executed. By June the Girondins had been ousted.

Counter-revolutionary forces were gathering in the provinces and abroad. A Committee of Public Safety was set up as chief organ of the government. Left-wing popular pressure brought laws on general conscription and price controls and a deliberate policy of de-Christianization. Robespierre was pressed onto the Committee as the best man to contain the pressure from the streets.

The Terror began. As well as ordering the death of the hated queen, Marie-Antoinette, Robespierre felt strong enough to guillotine his opponents on both Right and Left. But the effect of so many rolling heads was to cool people's faith in the Revolution; by mid-1794, Robespierre himself was arrested and executed, and his fall marked the end of radicalism. More conservative forces gained control of the government, decontrolled the economy, repressed popular risings, limited the suffrage, and established a five-man executive Directory (1795).