I am in the process of reading 'The Story of French' by Nadeau and Barlow. There's a chapter on how France was able to push their influence, during the renaissance, to get the world to switch to the metric system. Prior to developing the metric system, France had no standard for the pound; unlike England. This was the height of enlightenment in France, so the reformers wanted to replace the Gregorian Calendar with a metric time. I believe they wanted to call it the Republic Calendar; rather, the equivalent in french. So, they commissioned a poet to rename the months of the year, keeping twelve months of 30 days, with 5 or 6 ambiguous days at the end of the year. However, the major downfall was moving to a 10-day week which reduced the 'weekend' (not that it was called that) from 1 day out of a 7 day week to a 1-in-10. The plan was to have poetic names for the days of the week, but they felt that they were push their luck so instead they went with ordinal numbers.
The only country to actually use the calendar was, of course, France for 16(!?) years until Napoleon repealed it during his imperial reign.
https://en.wikipedia.org/wiki/Metric_time
Anyone, feel free to correct me. I, literally, just read about this (fascinating) subject a couple nights ago. I haven't had time to independently follow up on the topic, but I plan to do so soon.
Amendum: A better link, https://en.wikipedia.org/wiki/Decimal_time#France