How was the first day of the year determained?

Question

We all know that Jan 1 (Gregorian) is New Years Day, but how was it determined which day of the earth's cycle would be Jan 1st? Why did they not choose the Winter Solstice which is 8 or 9 days earlier? Who made the determination of which day would be the first day of the year?

Answer 1

The Romans continued to observe the new year in late March, but their calendar was continually tampered with by various emperors so that the calendar soon became out of synchronization with the sun.

In order to set the calendar right, the Roman senate, in 153 BC, declared January 1 to be the beginning of the new year. But tampering continued until Julius Caesar, in 46 BC, established what has come to be known as the Julian Calendar. It again established January 1 as the new year. But in order to synchronize the calendar with the sun, Caesar had to let the previous year drag on for 445 days.
-------------------------
During the Middle Ages 1 January retained the name New Year's Day (or an equivalent name) in all Western European countries (affiliated with the Roman Catholic Church), since the medieval calendar continued to display the months from January to December (in twelve columns containing 28 to 31 days each), just as the Romans had

Most Western European countries, except for a few Italian states, shifted the first day of their numbered year to 1 January while they were still using the Julian calendar, before they adopted the Gregorian calendar, many during the sixteenth century.

Historically, most calendar reforms have been made in order to synchronize the calendar in use with the astronomical year (either solar or sidereal) and/or the synodic month in lunar or lunisolar calendars.

Answer 2

Good question. For a long time the year 'began' on the spring equinox, which used to be March 25th, but that was still not on the first day of a month. The Roman Saturnalia took place at the end of the year when the days started getting longer, so maybe the year was said to begin after that blowout was over with.

There's an amusing website called badastronomy.com with an article called Happy New Year/Arbitrary Orbital Marker which discusses this.

Answer 3

When the Roman Catholic Church was powerful, Popes dictated things about the calendar. Being in Rome (except for the interval in Avignon), they used the Roman calendar which was based on the Sun (the Romans got it from Egypt) instead of the Lunar calendar used by the Hebrews.

Because of that, the most important date in their calendar (Easter Sunday) was mobile. In the lunar calendar, it was set on the 14th day of Nisan. It has been pegged as "the sunday immediately following the first full Moon after March 21."

In order to keep track of Easter (and other important dates), the Pope would assign the task to someone. At times, that person would be an expert, and strange things would happen.

For example, under Pope Gregory XIII, Christopher Clavius, a Jesuit/astronomer who was given the task, had determined that the date of the Spring equinox had drifted back by 10 days and devised a way to fix the problem. So the pope decreed that 10 days would be skipped, just like that (October 4, 1582 was followed by October 15, 1582) and years ending in 00 would not be leap years, unless they were divisible by 400.

At other times, the task was given to powerful people as an honour. For a while, the kings of France had the task of looking after the calendar. One of them changed the date of the start of the year from April 1 to January 1. From then on, those who continued to celebrate the New Year on April 1 were "April Fools".

Throughout history, the start of the year moved around: The Romans had it on March 1 (the month named after the god of war; prior to March 1, the roads were impracticable and you could not send any decent army to war). That is why "September, October, November and December" are named that way (7th month, 8th month, 9th month, 10th month)

Some of the Roman "pagan" religions had the religious year begin on January 1: Janus was a god with two faces, able to look both ways (he was the god of doorways and gates), so he could overlook the past year and the coming year. To conter tht, the early Roman Church started the year on December 25 (birth of Christ). For example, December 24, 421 would be followed by December 25, 422.
Another date to be used was Easter. That made thing worst, as this is not a fixed date.

PS:
As I am looking for the name of the king who changed it last, I found out that Julius Caesar (or for you Latin folks: IVLIVS CAESAR, pronounced kayzar) had changed the date to January 1 (from March 1) at some point.

In 1564, king Charles IX of France changed it from Easter to January 1. In 1564, Easter was on April 2 (Julian Calendar) and some "April Fools" wanted to celebrate New Year's eve on April 1.

This makes 1563 a very short year: 11 April 1563 to December 31, 1563 (265 days).

However, it is possible that Charles the Ninth's decree did not have an immediate impact outside France and Rome.

Another famous person who had the task of looking after the calendar is Dionysius Exiguus who calculated the years since Christ's birth. We are still using his count (e.g., 2007th year since the start of the era).

During the Frech Revolutionary government, the year began on Autumn equinox. All months had 30 days (3 "decades" of 10 days); there were 5 "free" days at the end of the year (6 on leap years) for celebrations.