who ruled france when the metric system was established
Ancien Régime
French Revolution
The French Revolution ( ) began in May 1789 when the Ancien Régime was abolished in favour of a constitutional monarchy. Its replacement in September 1792 by the First French Republic led to the Execution of Louis XVI in January 1793, and an extended period of political turmoil. 
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French Revolution [SEP] Introduction
The French Revolution ( ) began in May 1789 when the Ancien Régime was abolished in favour of a constitutional monarchy. Its replacement in September 1792 by the First French Republic led to the Execution of Louis XVI in January 1793, and an extended period of political turmoil. This culminated in the appointment of Napoleon as First Consul in November 1799, which is generally taken as its end point. Many of its principles are now considered fundamental aspects of modern Liberal democracy. The intellectual origins of the Revolution came from a global network of European and American 'patriots', who shared ideas and political principles, contacts accelerated by the American Revolution.