Q&A

Q: What's all this "new calendar"/"old calendar" business?

A: In 46 B.C., Julius Caesar introduced a new calendar to the Roman world. It was called the Julian calendar, and was used by the entire Christian world until the late sixteenth century. However, it proved to be impossible to synchronize this calendar precisely with astronomical phases, so gradually the date of Easter drifted away from the March equinox. This was a slow drift, about 11 minutes per year, that nonetheless accumulated significantly over the centuries, so by 1582, during the reign of Pope Gregory XIII, the calendar was about ten days off from where it had been during the Council of Nicaea in 325.

It was this Pope Gregory who authorized the calendar that bears his name in an attempt to bring the civil calendar into sync with the astronomical movements and keep it there. The first countries to adopt the new Gregorian calendar were the predominantly Roman Catholic ones: Italy, Spain, Portugal. Eventually, the Protestant countries--England, Germany, Denmark, the American colonies--went along, followed by east Asian countries.

Countries that were predominantly Orthodox didn't get on board until much later. The Orthodox Church itself, ever reluctant to adopt any change at all--especially one initiated by a Roman pope--didn't even consider the Gregorian calendar until the early 20th century, when a few Orthodox bodies decided that they wanted to be able to celebrate certain holidays with their Protestant and Roman Catholic brethren. So they adopted the new calendar despite the protests of other Orthodox bodies.

Today, calendar usage within Orthodoxy falls generally into three groups:

1) Those who have fully adopted the Gregorian calendar (in the U.S. this is by far the largest group).

2) Those who continue to follow the old Julian calendar, but remain in communion with churches on the new calendar (This is a smaller group in the U.S. but elsewhere outnumbers the first group).

3) Those who not only reject the Gregorian calendar, but also have broken communion with the churches that have adopted it (this is a very, very small group).

The church that Kathryn and I attend falls into the second of these three categories. What this means is that they celebrate feast days thirteen days after new calendar churches do. For example, Christmas is celebrated on January 7th by the civil calendar, and St Patrick's Day is on March 30th.

However, all Orthodox churches, whether on the old system or the new, celebrate Easter together every year. (Orthodox Easter is not thirteen days after Protestant Easter, but is calculated according to an entirely different system about which I know nothing. In 2009, Orthodox Easter will be celebrated 7 days after Protestant/Roman Catholic Easter)

Go here for further information:
The Julian and Gregorian Calendars
The Calendar of the Orthodox Church
The Orthodox Ecclesiastical Calendar