By the sixteenth century many learned Europeans realized that there was something seriously wrong with their calendar system. The calendar in use at that time was called the Julian calendar, named after the Roman emperor Julius Caesar (100 its adoption in 46 B . C . A small but important error marred this calendar system. The astronomers who designed the Julian calendar calculated the solar year to be 365.25 days long. In fact, it takes the earth 365.2422 days to complete its orbit around the sun. While this difference only amounts to 11 minutes and 14 seconds every year, each passing year compounded the error, increasing the gap between the dates on the Julian calendar and the astronomical events and seasonal changes of the solar year. For example, in 45 equinox fell on March 25 (see also Annunciation). By the time the Council of Nicea met in 325 A . D . to determine the date of Easter, spring equinox was falling on March 21.
As the centuries passed scholars debated the calendar problem, although nothing was done to correct it until the sixteenth century. In 1545 the Council of Trent empowered Pope Paul III to propose a solution to the dilemma. Investigators labored on the problem for forty years, until a Jesuit astronomer named Christoph Clavius submitted a viable program of calendar reform to Pope Gregory XIII. In 1582 Pope Gregory XIII officially adopted Clavius’s proposed reforms, resulting in a new calendar system known as the Gregorian calendar.
The researchers who devised the Gregorian calendar knew the true length of the solar year and based the new calendar around it. In order to correct the errors that had compounded over the years from the use of the Julian calendar system, Pope Gregory XIII decreed that ten days be eliminated from the calendar year of 1582. Thus, in that year October 5 was followed by October 15 in all lands that had adopted the new calendar. This brought the spring equinox back to March 21, the date on which it had occurred at the time of the Council of Nicea. Medieval calendar systems had also been plagued by the fact that the nations of Europe began their new year on different dates. The Gregorian calendar also declared January 1 to be New Year’s Day in an attempt to standardize the beginning of the European year.
Resistance to Reform
Although scholars agreed that the Julian calendar system was flawed, many European nations resisted the changes proposed by the Gregorian calendar. Religious controversies fueled this resistance. The Roman Catholic nations of Italy, France, Luxembourg, Spain, and Portugal switched to the new calendar system in the same year it was announced. Many Protestant nations hesitated to adopt the calendar for fear of seeming to accept the authority of the Pope. In addition, much of Orthodox eastern Europe viewed the proposed changes as out of step with their religious traditions. This meant that at the close of the sixteenth century, the nations that did adopt the Gregorian reforms were fully ten days ahead of those that did not.
Europe Adopts the New Calendar
By 1584 most of the Roman Catholic German states had adopted the calendar, along with Belgium and parts of the Netherlands. Hungary switched to the new calendar in 1587. Switzerland began making the changes in 1583 and completed them 229 years later, in 1812. More than one hundred years passed before the Protestant nations began to adopt the Gregorian calendar. Denmark and the German Protestant states did so around the year 1700. In 1752 Great Britain and her colonies converted to the Gregorian calendar system. Sweden followed suit in 1753. Japan joined the Gregorian system in 1873, and Egypt in 1875. Between the years 1912 and 1917 many of the eastern European states switched to the Gregorian calendar system, including Albania, Bulgaria, Estonia, Latvia, Lithuania, Romania, and the former Yugoslavia. China also embraced the Gregorian system during those years. Russia joined the club in 1918, just after the Revolution. Greece held out until the early 1920s, the last major European nation to adopt the sixteenth-century reforms.
At the time of its creation, the ten-day gap between the new Gregorian calendar and the old Julian calendar created a situation in which the peoples of Europe celebrated Christmas on different days. By the time England adopted the Gregorian calendar in 1752, the gap had crept up to eleven days. With the stroke of a pen English legislators ordered that September 2, 1752, be followed by September 14, 1752. Many ordinary people defied this change, fearful that it would adversely affect their livelihood in some way. Although many writers have reported that resistance to the new calendar took the form of riots and slogans, such as “Give us back our eleven days,” recent research has failed to find convincing evidence of these events. Instead, it appears that people resisted the change in less dramatic, more personal ways. Some refused to celebrate the feast days on the new Gregorian schedule and clung instead to the old dates, now known by different names (see also Glastonbury Thorn). For example, under the Gregorian reform the day that had been December 25 instantly became January 5. Many called January 5 “Old Christmas Day” or Christmas Day “Old Style.” Correspondingly, December 25 was known as Christmas Day “New Style.” By the nineteenth century Old Christmas Day had crept a day further away from the Gregorian calendar, falling on January 6, Epiphany. As the Julian calendar continued to drift away from the Gregorian calendar throughout the twentieth century, Old Christmas Day shifted yet another day forward in the Gregorian calendar, falling on January 7.
Some branches of the Orthodox Church have never accepted the Gregorian calendar. Their festival dates are still set according to the Julian calendar. Therefore, they observe Christian festivals on different dates than do most Western Christians. In Russia, for example, Orthodox believers celebrate Christmas on January 7. Orthodox Ethiopians and Egyptians also observe Christmas on January 7. (Seealso Ethiopia, Christmas in.)
Bellenir, Karen, ed. Religious Holidays and Calendars. Second edition. Detroit, Mich.: Omnigraphics, 1998. MacDonald, Margaret Read, ed. The Folklore of World Holidays. Detroit, Mich.: Gale Research, 1992. Muir, Frank. Christmas Customs and Traditions. New York: Taplinger, 1977. Poole, Robert. “‘Give Us Back Our Eleven Days’.” Past and Present 149 (November 1995): 95-140.
Encyclopedia of Christmas and New Year’s Celebrations, 2nd ed. © Omnigraphics, Inc. 2003