Why and how did the French Revolution take a radical turn?

WWHEN LOUIS XVI ACCEPTED THE NATIONAL ASSEMBLY’S CONSTITUTION in September 1791, a young provincial lawyer and delegate named Maximilien Robespierre (1758–1794) concluded that “the Revolution is over.” Robespierre was right in the sense that the most constructive and lasting reforms were in place. Yet he was wrong in suggesting that turmoil had ended: a much more radical stage lay ahead.

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The Figure of LibertyIn this painting, the figure of Liberty bears a copy of the Declaration of the Rights of Man and of the Citizen in one hand and a pike to defend them in the other. The painting, by female artist and ardent revolutionary Nanine Vallain, hung in the Jacobin Club until its fall from power. (Musée de la Revolution Française, Vizille/The Bridgeman Art Library)