The term A.D. stands for the Latin phrase ‘Anno Domini’ which translates into ‘In the Year of Our Lord.’ It is used predominantly in the Gregorian and Julian calendars to represent almost the current era or the time period after the birth of Jesus Christ.
Anno Domini: A Brief History
The Anno Domini system was developed by a monk named Dionysius Exiguus in the 6th century. The monk’s goal was to prepare a better table for calculating when Easter should be celebrated, based on a new 19-year cycle. At the time, the most widely used calendar was the Anno Diocletiani, or Diocletian Era, which started from the rise to power of Emperor Diocletian, a cruel persecutor of Christians. Dionysius found this inappropriate and began his calendar ‘ab incarnatione Domini’, which translates to ‘from the incarnation of the Lord’.
Dionysius’ new timeline mark was not instantly adopted widely. It wasn’t until centuries later, during the Carolingian Renaissance, that the usage of Anno Domini started to spread across the western Europe. By the 10th century, many religious and official documents of Western Europe had started to timestamp with years after Christ’s birth.
Use of A.D.
When denoting dates, A.D. is positioned before the year number in the day-month-year format. For example, A.D. 2022. Conversely, when following a month-year or year only format, A.D. is placed after the year. Like, January, 2022 A.D. or 2022 A.D. This is the standard taught by the Chicago Manual of Style. However, it is not uncommon to see the placement of A.D. vary between sources or based on personal or organizational preferences.
A.D. and B.C.
On the other hand, the term B.C., which stands for ‘Before Christ’, is used to denote periods before the birth of Jesus. The usage of both these systems together separates history into two broad eras – B.C. and A.D. Although this system is widely used around the world, it’s important to note that many cultures and religions have their own calendars and systems of measuring eras which doesn’t use Anno Domini.
Alternative to A.D. and B.C.: The C.E. and B.C.E. System
The increasingly common trend today, especially in academic and scientific literature, is to use B.C.E. (Before Common/Current Era) and C.E. (Common/Current Era) as alternatives to B.C. and A.D. respectively. This change has been made, mainly due to the effort to minimize the Eurocentric bias, and for a universal system of dating that is more neutral and inclusive to all cultures and religions.
Even after witnessing various transformations over hundreds of years, A.D. continues to be a commonly accepted way of referring to the years following the supposed birth time of Christ. However, while using A.D., we should be conscious of its historical development and modern alternatives that seek to promote inclusivity and neutrality.