Explanation: During the ancien regime of the French Monarchy, the population was split into three groups for 'representation' - the first estate, consisting of the Catholic clergy who were not only tax-exempt, but ALSO empowered to tax the peasantry on their lands; the second estate, consisting of the nobility, also largely tax exempt; and the third estate, consisting of literally everyone else.
After a financial crisis caused by runaway spending on military adventures and luxuries for the royal family, the three estates were called together to approve new taxes to be levied on the French people - obviously, still exempting the priesthood and nobility!
The representatives of the Third Estate were not happy about this, and after some quarreling over representation (as the First and Second Estates could outvote the far-more-numerous Third Estate), they declared themselves the representative of the French people - the first step of the French Revolution which would eventually lead to the (literal) decapitation of the monarchy and its replacement by the First French Republic. Vive la France!