How did the Third Estate become the National Assembly in June 1789?

The transformation of the Third Estate into the National Assembly was a pivotal moment in the French Revolution, driven by a fundamental dispute over voting procedures within the Estates-General.

When the Estates-General convened in May 1789, the Third Estate demanded that voting occur by head rather than by order. Voting by order would have allowed the clergy and nobility to consistently outvote the commoners, effectively vetoing any meaningful reform.123

On June 17, 1789, following weeks of deadlock and inspired by the ideas of Emmanuel-Joseph Sieyès, the deputies of the Third Estate took a decisive step by proclaiming themselves the National Assembly, asserting their authority to legislate for the French nation.43

This defiance escalated when royal officials locked the deputies out of their meeting hall on June 20. In response, the deputies gathered at a nearby indoor tennis court, where they swore the Tennis Court Oath, vowing not to disperse until they had established a written constitution for France. Faced with this solidarity, King Louis XVI eventually relented, ordering the remaining clergy and nobility to join the Assembly.123