>So I find it entirely believable that there were multiple “standards” for Roman numerals that spanned different regions and periods of time.
That indeed seems to be the case. Apparently it largely standardized at some point in the Middle Ages as usage was decreasing. Although I can't find a reference, it's logical to assume given the timeframe and place that the Church probably had something to do with the standardization whether formally or otherwise.
That indeed seems to be the case. Apparently it largely standardized at some point in the Middle Ages as usage was decreasing. Although I can't find a reference, it's logical to assume given the timeframe and place that the Church probably had something to do with the standardization whether formally or otherwise.