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First country to adopt the metric system

First country to adopt the metric system
Who
France
What
First
Where
France
When
1799
The metric system was first conceived during the French Revolution (c. 1790s) in an attempt to modernize antiquated traditional forms of measurement, which were often open to misinterpretation. The system was provisionally rolled out in France in 1795, but was only made official in 1799 when standards were established for a "metre" and "kilogram".