Happy Birthday JSB
Johann Sebastian Bach birthdays - March 21 AND 31 - forensic proof

Johann Sebastian Bach - BIRTHDAY FUN FACTS

BORN March 21, 1685 (Julian / Roman Calendar) AND March 31, 1685 (Gregorian calendar).

bachmonster and monsters of bach wish Johann Sebastian Bach a happy birthday Mar 21 AND Mar 31

HOW CAN BACH HAVE TWO BIRTHDAYS?

When Johann Sebastian Bach was born in 1685 in Protestant Germany, and where the Julian (Roman) calendar (created in 45 BC) was still being observed, his family's calendar showed March 21.  

However, it was long known that the calendar dates had been 'drifting' for centuries; a day every 128 years it turns out. The longest and shortest days of the year were now about 10 days off the original ancient calendar dates, and Bach's birth likewise was uncertain.  

So why wasn't Johann's birthday recorded per the more accurate Gregorian calendar date? 

About 100 years before, the Catholic Pope Gregory and his Italian astronomer scientists established the more precise calendar in the year 1582. 

However, England and other Protestant countries and regions were slow to acknowledge any Catholic wisdom. They did eventually adopt the more precise Gregorian calendar, with the Lutheran Protestants in Germany officially changing over in 1700, and here's an important detail, with the legal stipulation that all Julian / Roman calendar dates prior to Dec. 31, 1699 would remain valid.  

Since JS Bach was a Protestant Lutheran born in that time frame, he always considered his birthday to be an unaltered March 21 date, and was legally allowed to claim that, even after his 15th birthday. 

And now, Bach's birthday lined up with the start of Spring: 

Johann was pleased to find that his March 21 date on the new calendar now shared the beginning of Spring, and this may have helped to shape his preference to hold onto the original date.

Since the calendar days jumped ahead, when you readjust to the correct location in Earth's path around the sun, the start of Spring (vernal equinox) landed (and still does) on any one of 3 dates any given year, March 19, 20, or 21, pretty much right on his birthday every year. At least so long as his birthday was still on March 21...  Never mind that the actual solar position is really at Gregorian calendar's March 31.

Bach also liked the coincidental alignment of his surname with the Mar 21 birthdate: 

If you take the numbers from his original DD-MM-YY birthday, and match the numbers to their corresponding letters of the alphabet:

21-3-85 corresponds to the letters B A C H E

Okay, ignore the E, pretty close.  So, now you're asking yourself,

Why not just celebrate both birthdays, and what about the days in between? 

I contend that it is fundamentally proper to celebrate the music and life of JSB from his personally perceived, legally recognized birthday date of March 21, AND ALSO the somewhat astronomically correct positional date of March 31, and all dates between, linked as an 11-day birthday decad+.  

How should I celebrate Bach's Birthday? 

You may decide to drink some 'bock' beer, you may choose to look up this JSB character on your interwebs, or just "Rock out with your Bach out". 

As for me, I'm playing my Bach arrangements with my group, Monsters of Bach, every day with occasional unadvertised hit-n-run concerts in strategic Silicon Valley locations ... see you out there.