Final answer:
In 1789, the Third Estate, primarily made up of the middle class and commoners in France, split from the Estates General and declared themselves the National Assembly. This was a critical step towards the French Revolution, asserting the sovereignty of the people and triggering key revolutionary events.
Step-by-step explanation:
In 1789, the frustrated Third Estate in France broke away from the Estates General and began calling themselves the National Assembly. The Third Estate primarily consisted of the middle class and commoners who were frustrated by their lack of influence and the unfair tax system that largely fell on their shoulders. Despite representing the vast majority of the population, their proposals were often vetoed in the Estates General where each Estate had one vote and the First and Second Estates, composed of the clergy and nobility, often voted together.
Discontented and seeking reform, they detached from the Estates General to form the National Assembly. This act was a radical political step towards asserting the sovereignty of the people against the monarchy. It triggered a series of events, including popular uprisings, seizure of important sites like the Bastille, and protests against taxes that marked the beginning of the French Revolution.
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