With all due respect, Julian is actually Julius Caesar and Greg is Pope Gregory XIII, both of Rome, both highly influential in their respective times and both with an eponymous calendar.
It was at the behest of Julius Caesar to better serve his expanding empire that a new Roman calendar was adopted in 709 BC. Based on the solar calendars used by the Greeks, Egyptians and Babylonians, the new calendar was adapted by Alexandrian astronomer Sosigenes and consisted of a system similar to what we have today, using the solstices and equinoxes to determine months and seasons.
Controversy entered the picture when it came time to determine the start of the New Year. Caesar being Caesar insisted that either the vernal equinox in March or the winter solstice in December signal the beginning. The Roman Senate flexed its veto powers, though, and being good public servants, declared January 1st, the opening day of their annual session, to begin the Roman civil year. Ever the savvy politician, Caesar bowed to the Senate’s wishes, but he still got calendar name rights.
Senate edict, or not, New Year’s Day in the Roman world was still more closely associated with the vernal equinox. As Christianity became the official faith of Rome, religious holidays coincided with those associated with the empire’s Pagan past. The Feast of the Annunciation (the Angel Gabriel’s announcement to Mary that she would conceive the Son of God) on March 25, nine months prior to Christmas Day, commenced the springtime new year. It is no coincidence that Easter, too, should be celebrated at this time of new life. In fact, it was Easter that brought about the change in calendars.
Now Greg enters our story. According to The Julian and Gregorian Calendars by Peter Meyer “… after about 131 years the calendar is out of sync with the equinoxes and solstices by one day. Thus as the centuries passed the Julian Calendar became increasingly inaccurate with respect to the seasons. This was especially troubling to the Roman Catholic Church because it affected the determination of the date of Easter, which, by the 16th Century, was well on the way to slipping into summer.”
In his 1582 reforms, Pope Gregory XIII invoked an edict by the First Council of Nicaea which in 325 AD declared that Easter must correspond with the Vernal Equinox. To reestablish this precedent in light of Easter’s wondering into June, the Gregorian calendar was established, deleting 10 days from the calendar, readjusting leap years and creating a strict determination of the dates on which Easter would fall.
Most of Western Europe implemented the Gregorian calendar over the next 150 or so years, but this still did not establish a universal New Year’s Day. The significance of either the winter solstice or vernal equinox in various locales was more likely to determine the commencement of the New Year, which could be observed on March 1, March 25, December 25 or January 1. (Confusing, to say the least, for champagne sales, but that’s another post.) England and its colonies joined the Gregorian club in 1752, declared January 1st to be the New Year’s Day and the rest of Western Europe followed suit. The Greek and Eastern Orthodox Churches remained on the Julian system, but that’s way too complicated to get into here.
January 1st is also significant in that it commemorates the Feast of the Circumcision of Christ, 8 days after Christmas Day which is also 4 days after the Winter Solstice. This once again illustrates Rome’s fine ability of folding the pagan rituals of the empire’s conquered western colonies into its Christian embrace.
Given New Year’s contemporary lay observance, it’s interesting to note the Church’s involvement in January 1st's eventual selection as the start of the year. It is the melding of the secular and the sacred that has given us so many holidays and celebrations. And where would we be without Julius and Greg? Be sure to give them a clink of the glass as you toast 2010!