The Reason 11 Calendar Days Were Skipped In 1752
Our calendar year isn't always so straightforward, with leap years and lunar holidays, but no one currently alive has ever had to skip over an entire week of the year. That's exactly what happened to British residents in 1752, when September 2 became September 14 overnight (via Mental Floss). The sudden time traveling was expected and largely accepted — perhaps not by children whose birthday fell in between the dates — and stemmed from an act passed by Parliament that had been decades in the making.
The confusion began when Pope Gregory XIII learned that the length of a year was 11 minutes shorter than previously thought. Though it doesn't seem like a huge difference, those 11 minutes add up significantly over long periods of time, and the Pope was concerned that Easter no longer fell under its original day. He proposed a new calendar, the Gregorian calendar, in 1582 to take over from the Julian calendar. Most of Europe heeded the Pope's call — but Britain did not.
Britain wasn't the last to switch
Centuries passed, and the consequences of Britain's decision to stick with the Julian calendar were apparent. By the 1700s, the Julian calendar was more than 10 days ahead of its Gregorian counterpart, and British citizens had taken to writing two dates on their letters (via Mental Floss). By 1750, the Calendar (New Style) Act was passed through Parliament, declaring all British territories, including the American Colonies, would have a short 1751, and then skip 11 days in September 1752.
Reaction to the change was one of annoyance and begrudging acceptance. According to Historic UK, citizens were peeved at having to celebrate their birthdays and major holidays on different days of the year, and the topic was ripe for political debate. There were even reports of riots in the streets demanding their "lost" eleven days back, though most modern historians believe this to be exaggerated or complete myths. Britain was not the most stubborn in the face of the change: Russia and Greece both waited until the 20th century to switch over, the latter doing so in 1923; those countries had to skip 13 days. Now, most of the world acknowledges the Gregorian calendar, and hopefully, we won't have to skip over any more weeks of our years.