  == The Ultimate Pi Day Of History? ==  Some claim The “ultimate” pi moment occurred on March 14, 1592, at 6:53 AM and 58 seconds.  Here are some facts I have assembled to see if this moment was possible. *The first actuate clock with a minute hand and seconds was invented by Jost Bürgi in 1577. Only a handful of astronomers could of had these.  *Ludolph van Ceulen published 20 digits of Pi in 1596. At least 11-16 digits were known before his time. *The Gregorian Calendar was inaugurated in 1582 and used by several European countries. Increased talk of dates and times due to the conversion may have helped.    It’s quite possible that some mathematician with access to one of Bürgi's rare clocks could have made the Pi Day connection to 10(or 12) digits, but the closest anyone else could get would be 3/14/1592. However, it really doesn’t matter because the date formats such as mm/dd/yyyy (or dd/mm/yyyy) weren’t in use until modern times. This pretty much rules out any possibility of anyone realizing the significance of 53 minutes past 6 o-clock, on the 14th day of March, 1592.   