The French Revolution was opposed by neighboring countries that feared that unrest would spread across Europe. A Committee of Public Safety was set up in France to defend the revolution, and they executed any person who might oppose the committee. In fact thousands of people who were thought to threaten this new regime were put to death by the recently invented guillotine.

This period became known as the Reign of Terror. It lasted for about a year and during this time around 18,000 people was put to death. The French aristocracy was almost entirely wiped out, together with any political opponents of the regime. The Reign of Terror finally came to an end when the head of the Committee of Public Safety, Robespierre, was accused of treason.