The reign of Louis XVI (1774-93), in hindsight, marked France's last opportunity to deal with its myriad of problems, financial, social, and political, and thus stave off, if not totally prevent, revolution from breaking out.
The French Revolution turned out not only to be a critical event in French history, but indeed in European and World history too.
The threat of revolution had been building for decades under the ruling House of Bourbon. Louis XVI, by character, was ill prepared to deal with the worsening crises of his reign.
Revolution finally arrived on the streets of Paris on 14th July 1789. The event which triggered it was the Storming of the Bastille Prison. In itself not an oversignificant event. Louis even wrote in his diary for that day, 'rien', nothing.
Yet the Revolution had arrived and spread across the country. It took a violent and bloody turn in 1793/4, under Robespierre, in what has become known as The Reign of Terror.
There were many twist and turns along this revolutionary path until some stability and normality was restored by Napoleon Bonaparte. But, in the end that stability came crashing down in military defeat, not once but twice, in 1813 and 1815 at Leipzig and at Waterloo. The Bourbons then returned to power, if only briefly (1814-48); and thus the question as to when the Revolution finally ended is a subject of much heated debate.