On October 4, 1582, Catholic Europe went to bed and woke up ten days later. Pope Gregory XIII had ordered the deletion of October 5-14 to correct 1,600 years of accumulated drift in the Julian Calendar — a drift of just 11 minutes per year that had compounded into an 11-day error in the date of the spring equinox. This episode of Sidequests covers the Julian-to-Gregorian calendar shift: the elegant mathematics behind the fix, the legal and commercial chaos the deleted days created, why Protestant countries refused to adopt a Catholic calendar innovation for over a century, and why it took nearly 400 years — until Greece switched in 1923 — for the entire world to finally agree on what day it was.
","author_name":"Keith Conrad"}