In modern times, everyone knows that a year is 365 days long (with the occasional Leap year in place to keep things nice and tidy). While this seems obvious to us all today, it turns out that making a calendar that stays properly synced up with the seasons is much harder than many people would imagine. Throughout human history, there have been quite a few attempts to create an accurate calendar, all of which have had some advantages and disadvantages.

Today, most of the world uses the Gregorian Calendar, which was made the standard in 1582 by Pope Gregory XIII. Before that, most of the world used the Julian calendar, made by Julius Caesar. Both of these are pretty accurate options (with the Gregorian calendar much more precisely keeping the calendar in line with the Earth’s actual position on the sun).

While the Julian calendar has a few issues, it was a massive leap forward compared to the options used before that. Prior to Julian Caesar, Rome used a 10-month calendar that lasted just 304 days (it was a lunar based calendar). This resulted in the seasons not lining up with the calendar very well at all after just a few years.

To try to solve for this, Rome began including Mercedonius, an ‘extra’ month that was added in when needed to counteract the season drift on the calendar. Unfortunately, they did not have any set rules on when the month of Mercedonius would be used. The Pontifex Maximus as well as the College of Pontiffs could add this month in whenever they decided it was necessary.

To nobody’s surprise, this power was abused. If a powerful politician needed some extra time in office, they could just add in an extra month, for example.

Then, Julius Caesar decided to solve this problem and he got to work on making the Julian calendar. Suetonius was a Roman historian who wrote Life of Julius Caesar, and in this book he explained:

“Then turning his attention to the reorganization of the state, he reformed the calendar, which the negligence of the pontiffs had long since so disordered, through their privilege of adding months or days at pleasure, that the harvest festivals did not come in summer nor those of the vintage in the autumn; and he adjusted the year to the sun’s course by making it consist of three hundred and sixty-five days, abolishing the intercalary month, and adding one day every fourth year.”

While this went a long way toward making sure the seasons would stay aligned with the calendar, there was a problem. When this new calendar was started, the seasons were already out of whack.

ShutterstockSo, to fix this issue Julius Caesar had to use his power to add in some extra time to the year. Suetonius explains:

“Furthermore, that the correct reckoning of seasons might begin with the next Kalends of January, he inserted two other months between those of November and December hence the year in which these arrangements were made was one of fifteen months, including the intercalary month, which belonged to that year according to the former custom.”

This took place in the year 46BCE. With the extra months added in, that year was actually 445 days long, making it the longest year in history. Historians have started referring to it as annus confusionis, which means the ‘year of confusion’ in Latin.

An appropriate name for a truly crazy year.

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