Anno Domini (AD) – Meaning and History

Anno Domini (AD) – Meaning and History

Anno Domini (AD) is a Latin phrase that means "In the Year of Our Lord." It is used to label years in the Gregorian and Julian calendars, marking the years after the traditionally recognized birth of Jesus Christ.

Who Introduced Anno Domini?

The Anno Domini dating system was introduced by Dionysius Exiguus, a Christian monk and scholar, in 525 AD. He developed this system to replace the older Diocletian Era, which was based on the reign of Emperor Diocletian, known for persecuting Christians.

How Does It Work?

Years before Christ’s birth are labeled as BC (Before Christ).

Years after Christ’s birth are labeled as AD (Anno Domini).

There is no "Year 0"—the system moves directly from 1 BC to 1 AD.

Why Was AD Created?

Dionysius wanted a Christian-centered dating system, moving away from pagan references. His system was later popularized by Bede the Venerable in the 8th century AD and eventually became the dominant dating system in Europe.

Relation to CE (Common Era)

Today, many scholars and secular historians use CE (Common Era) instead of AD and BCE (Before Common Era) instead of BC to maintain neutrality, but both systems represent the same timeline.

Would you like to explore how different civilizations tracked time before AD/BC?