The Estates-General was the traditional assembly of France. It consisted of three "estates" or classes - The nobility, the clergy, and the common people. It was not usually called to order. I am not sure of the specific number, but when Louis XVI called the Estates-General to order in May of 1789, it was the first time in a while.
The calling of this body led to the Tennis Court Oath and the National Assembly. This was the beginning of the French Revolution.
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