Trivia time: George Washington’s birthday. [cue final Jeopardy music]. What is February 22^nd? Straightforward right? Well, it’s a bit more complicated than that. When Mary Washington delivered little George, if there was a calendar on the wall of the cabin at Pope’s Creek Estate it would have read: February 11^th. If that’s not confusing enough, at the time everyone would have said it was the 1,731^st year of our Lord, but now we say he was born in 1732. So when is George’s birthday: 2/22/1732 or 2/11/1731? The correct answer is: both. Calendars are fickle things—they’re always changing on us—and the confusion over George Washington’s birthday (and countless other historical “dates”) is entangled in Roman ivy, Papal lace, and Protestant damask.

The western calendar may seem obvious enough: the sun rises and sets 365 times in the course of earth’s journey around the sun. As we count our days it should take the same number to get back to where we started—wherever that starting place is. From one vernal (spring) equinox to the next there should elapse the same number of days each year. But that’s not always the case. To those who first started keeping track of these astronomical periods way back in pre-history, it was very quickly apparent that 365 isn’t the right number. In fact, ancient astronomers estimated that the sun rises 365.25 times in the course of one year, and so any attempt to “fix” a particular cyclic phenomenon, like the vernal equinox, to a particular recurring “day” out of 365 was impossible. Every four years your “vernal equinox day” was off.

So why does it matter? Scientifically it doesn’t, but the meaning attached to a particular “day” is an integral part of being human. Who doesn’t know their birthday (or some other yearly personal celebration like a patron saint’s or “name” day)? And isn’t knowing the first day of spring crucially important for human economic wellbeing? When should I plant my crops? When can I expect the coming of the western trade winds? All of these earthly phenomena are deeply tied to celestial events. Their cyclical nature is one of the primary factors of civilization, and reckoning the pattern—with a calendar—was (and still is) vital. Each world civilization developed its own system, but in all of them, that quarter of a day, a mere six hours, can wreak havoc. Even in the course of one’s lifetime, fixed astronomical points can deviate up to fifteen days with a 365-day calendar.

The Romans, in their customary fastidiousness, could not let astronomical time overcome their mastery of it. During the Republic (509 to the 40s BC), Roman magistrates regularly “fixed” or adjusted the calendar so that dates which had wandered up to fifty days were resynchronized to their accompanying astronomical event. For them as with many cultures, time and the calendar were religious matters.

Roman Calendar from Caere

Days were set aside for specific prayers and sacrifices, business could only be conducted on days appointed by religious custom, and so “being right” mattered; the Roman/human calendar had to match the celestial calendar of the gods. For a vast array of reasons by 45 BC, the Roman calendar was quite “broken.” Every so often, calendar officials added an intercalary month, making the year 377 or 378 days long and catching the calendar back up to the earth and the sun.

The calendar wasn’t the only thing malfunctioning in Rome by the 40s BC. The vast and complicated network of voting assemblies and magistracy of the Republic couldn’t stop aristocrats from bloody political strife. Roman Civil War raged across the Mediterranean and one man emerged atop Rome’s sanguine empire: Julius Caesar. Ubiquitous today for his conquest of Gaul and immortalized assassination, Julius Caesar’s most enduring achievement, however, is far less known: the Julian calendar.

As dictator, Caesar employed a vast number of astronomers and priests to make a new calendar for Rome. Now the year would be fixed at 365 days, and instead of the periodic intercalary month, every fourth year a “leap” day was added, adjusting for that pesky .25. It seems scientific enough, but how would the Roman people respond? The traditional calendar, set by the gods, the thing which determined daily routine, something Romans knew from childhood, a thing whose peculiarities were part of the very definition of time, was swept away by a self-imposed dictator. To scholars (and many priests) the new calendar brought clarity, but to those whose understanding of time was far less sophisticated, Caesar was messing with the very structure of the cosmos.

The Julian reform of the calendar, imposed from on high by a political and religious authority stretching the bounds of his earthly power, eventually did “take,” but his calendar isn’t what’s hanging on our walls today. For over a thousand years Roman pagans and then the Christian world used Caesar’s understanding of time, but there was still something wrong. By the 1500s the calendar had drifted “off” by ten days. Astronomers had the answer: the year is not 365.25 days long, but actually 365.2425. It took sixteen centuries for this 0.002% error to become an issue, but an issue it was, nonetheless. The counterreformation pope, Gregory XIII, took the bull by the horns. The calendar was just as sacred to Christian Europe as it was to pagan Rome and determining the date of Easter (a subject for another day), was deeply tied to the vernal equinox. It was essential to get that “date” right. The scientific and astronomical dream-team assembled by Gregory figured it out. It’s probably best to cite the US Naval Observatory since science isn’t my strong-suit: “[In the Gregorian Calendar,] [e]very year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400.” That means that 1900 wasn’t, but you’ll remember 2000 was a leap year since it was divisible by 400.

But what does all of this have to do with George Washington? As Gregory XIII was promulgating his bull, England was protestantizing herself. The new establishment in the British Isles, like many Protestant principalities on the continent, would not submit to popish dictates on time. The English parliament saw the new calendar as a papal plot: to them, the pope only had control over time in his territory. The government, not a superstitious religion, dictated English time. Slowly but surely, the rest of Europe adopted Gregory’s reform and most of the German protestant states were on the Gregorian standard by 1699. England and her colonies were the only hold out by the 1750s (save Russia and the orthodox churches). It was getting a bit embarrassing, if not confusing. To the newly “enlightened” Europe, time was surely a scientific matter, not a religious or political one, and even if spread by the pope the proof was in the pudding: it was scientifically sound. So George, born under the Julian calendar (“off” by eleven days), got a new birthday in 1752 when the English and their colonies “skipped” eleven days in September to match the Gregorians: Wednesday the Second was followed by Thursday the Fourteenth. New Year’s was no longer March 25^th, but January 1^st. Since president-to-be Washington was born in February, under the old style he was born before New Year’s 1732. With Gregory’s January New Year’s, George got a new birth year too.

The English people did not take this well. Papal politics aside, it appeared in 1752 that the government was taking eleven days from the people. Riots broke out under the motto “Give us our eleven days!” It took quite some time to explain that days can’t be stolen, but a culture’s reckoning and understanding of time can be far from scientific.

Hogarth, “An Election Entertainment.”  (1755) Note the placard on the floor: “Give us our eleven days.”

References:

Coyne, SJ, C.V., M.A. Hoskin, and O. Pedersen, eds. 1983. Gregorian Reform of the Calendar: Proceedings of the Vatican Conference to Commemorate its 400^th Anniversary. Vatican City.

Feeney, D. 2007. Caesar’s Calendar: Ancient Time and the Beginnings of History. Berkeley.

Poole, R. 1998. Time’s alteration: Calendar reform in early modern England. London.

Westman, R. 1980. “The astronomer’s role in the sixteenth century: a preliminary study.” History of Science 18: 105-49.

United States Naval Observatory. 2015. “Introduction to Calendars.” http://aa.usno.navy.mil/faq/docs/calendars.php.