In 1791, the French Revolution was in full swing when the metric system was proposed as a much needed plan to bring order to the many conflicting systems of weights and measures used throughout Europe. It would eventually replace all the traditional units (except those for time and angle measurements).

The system was adopted by the French revolutionary assembly in 1795; and the standard meter (the first metric standard) was adopted in 1799. But not everyone agreed with the metric system’s use, and it took several decades before many European governments adopted the system. By 1820, Belgium, the Netherlands, and Luxembourg all required the use of the metric system; France, the originators of the system and its standards, took longer, finally making metric mandatory in 1837. Other countries like Sweden were even slower: They accepted the system by 1878 and took another ten years to change from the old method to the metric.