Nayrouz
The chronology of the Coptic Orthodox Church begins when Diocletian became Roman emperor in 284 AD. His reign was marked by torture of Christians to force them to deny their faith, as well as by mass executions, especially in Egypt. It is believed this time was one of the worst times that the Coptic church faced, known to believers as "the martyrdom era". Hence, the Coptic year is identified by the abbreviation A.M. (for "Anno Martyrum" or "Year of the Martyrs"). It should not be confused with the A.M. abbreviation used for the unrelated Jewish year, which is "Anno Mundi" ("year of the world").
The Coptic year
The Feast of Nayrouz marks the first day of the Coptic year.