Final answer:
The Third Estate bore the majority of the tax burden under the Old Regime in France, which was a primary cause of frustration that led to the French Revolution.
Step-by-step explanation:
Under the Old Regime in France, the majority of taxes were paid by the Third Estate, which comprised about 97% of the population.
This social class included peasants, the urban poor, the middle class (burgers), and professionals such as merchants and bankers. While the First Estate (clergy) and the Second Estate (nobility) enjoyed various privileges and were largely exempt from taxation, the burden of taxation fell disproportionately on the Third Estate, exacerbating economic inequality and contributing to social unrest that led to the French Revolution.
The Third Estate's grievances were not just about taxation but also about political disenfranchisement, as they had less representation in the Estates-General compared to the privileged Estates. The National Assembly, formed by the Third Estate, took steps to reform taxation and address the economic crisis.
This led to significant events such as the storming of the Bastille and eventually, the fall of the monarchy and the establishment of a more equitable social structure.