Once upon a time in the West, spring marked the New Year. The original Roman calendar ended the year with Februarius, a month of repentance and restoration before the Ides of March marked the New Year. But the Republic’s civil calendar began in January when newly elected consuls assumed office, so in 153 BC, officials simply rewrote things so that popular life matched with the bureaucracy. There were still problems, however. The lunar cycle seemed to suggest periods of roughly twenty-nine or thirty days, as in the Egyptian calendar, probably the world’s first. The period of earth’s rotation, however, was ever so slightly off, and lunar calendars slowly crept out of true with the actual cycle of the seasons. The Romans dealt with it by occasionally intercalating an extra month, but the process was complicated. The pontiffs who set the calendar were persuadable; a well-rewarded nudge here or there could affect the results of an election or keep an incumbent in office a while longer. When Julius Caesar seized control, he decided that enough was enough and converted to the Julian calendar. Caesar added 90 days to the year to get the seasons back in true; his system then relied on set sequence of 31- and 30-day months, with a short February expanded by a day every four years to adjust for the the fact that the year is a little more than 365 days long. Caesar did not renumber the years in his honor; the month of July was presumably enough reward. There are other choices Caeser could have made, as society’s have produced a dizzying variety of calendars. The Indian calendar is solar, but the Balinese calendar relies on separate lunar and solar measures. The Mayan calendar had concurrent systems involving 13- and 20-day weeks, with five holidays at the end of the year. The Chinese calendar, like the Jewish calendar, tracks both a solar year and lunar months. But Caeser’s choice was a reasonable one. It might have been perfect if the year was precisely 365 and one quarter days long. However, it’s just slightly shorter than that, so as the centuries passed and the leap years mounted, the seasons slowly began to drift again. This was important to the Catholic Church (not least for the calculation of Easter), and as early as the 1470s, the Pope was talking to astronomers about calendar reform. In 1582, under Pope Gregory XIII, Catholic Europe lopped nine days out of October. Protestant Europe slowly followed suit; by 1752, England was 11 days out of alignmet with most of Western Europe. The calendar riots that Hogarth "Election Entertainment" series may never have resulted in angry cries of "Give us back our eleven days!", but they must have been confusing. Umberto Eco used the confusion between Gregorian and Julian calendars as a plot point in one of his novels, and Robert Poole suggests that disputes over the date may have led to the decline of the observation of Christmas.

Religious observations remained tied to the calendar. Countries with large Orthodox populations remained on the Julian calendar much longer than anywhere elsewhere in Europe; Greece, for example, didn’t switch to the Gregorian calendar until 1924. The calendar reform provoked schism, with Old Calendarists Orthodox sects asserting that the Julian calendar remains the correct means of calculating holidays and that the Gregorian calendar represents a dangerously secular innovation. It’s nothing compared to the French revolutionary calendar, however; created by Gilbert Romme, the rather bizarre calendar divided twelve months into three weeks of ten days each. Before Philippe François Nazaire Fabre d’Églantine met the guillotine, he gave the months their wonderful names: Germinal, the month of seeds; Nivôse, the month of snow; Messidor, the month of harvest. The five days left over could be spent in cheerful contemplation of Man’s works at a Temple of Reason. The revolutionary calendar was a pernnial one — a given date was the same day of the week year after year. The calendar proved much less successful than the rest of the metric system, and shortly after Napoleon’s coronation (on 18th of Brumaire, VIII), it was abolished. Thanks to the calendar’s universality, however, a copy printed in the mid-1980s is as useful today is it was then.

The French revolutionary calendar was perhaps the last stand for secular calendar reform; two hundred years from now, Jews, Muslims, Hindus, and Orthodox Christians will all still be calculating holidays based on their traditional calendars, and we’ll still be trying to figure out if our birthdays fall on a Monday. But give a nod to those valiant backers of perennial calendars, however. They might have been bad for the makers of Day Planners, but their ideas make a certain amount of sense, and there is one benefit that Elisabeth Achelis, a follower of Melville Dewey, may not have anticipated. Hshe ad only been able to push through her World Calendar Association‘s 1930 proposal to make the year 364 days, precisely 52 weeks, long, it would have given the world one merciful day off the books to recover from our New Year’s Eve hangovers.