Re: Uniplex "my God, it chills me just mention the dark lord's name,"
Do you correct for locality? For any area controlled by England, the Julian to Gregorian calendar switch took place in 1752. Various other countries made the switch as late as 1923. The Orthodox churches still haven't converted.
You are the first one in over 30 years to even ask the question and the answer is no as it is very rare for a business system to need a date before about 1950.