Final answer:
The event where the European people turned against their king and executed him following the American Revolution was the French Revolution, during which King Louis XVI was executed in January 1793.
Step-by-step explanation:
Event Following the American Revolution
The event that occurred in Europe following the American Revolution where the people turned against their king and executed him was the French Revolution. In January 1793, the French king Louis XVI was executed. The period following his execution became known as the "Terror."
During this time, the revolutionary government violently purged perceived enemies, which included King Louis XVI and Queen Marie Antoinette, in an attempt to establish a new social and political order. This era is characterized by extreme changes, such as the abolition of dynastic succession, assaults on Catholicism, and the establishment of the Cult of the Supreme Being.
The French Revolution was spurred on by the ideas and success of the American Revolution but differed significantly from it. Unlike the American Revolution, which was a colonial independence movement, the French Revolution aimed to completely overhaul the existing French monarchical structure, including the execution of the king and a wide-reaching attempt to enact social changes within France itself.