The Armenian Apostolic Church (Armenian: Հայ Առաքելական Եկեղեցի), also called the Armenian Orthodox Church or the Gregorian Church, is the world's oldest national church[1][2] and one of the most ancient Christian communities.[3]
The Kingdom of Armenia was the first state to adopt Christianity as its official religion, when St. Gregory the Illuminator converted Armenian King Tiridates III and members of his court.[4][5][6] That occured in the early 4th century and is traditionally dated to 301 (after Mikayel Chamchian 1784). The church teaches that Gregory was imprisoned by Tiridates in an underground pit, called Khor Virab, for 13 years, and then treated Tiridates of an incurable disease, which made him accept Christianity.
The church's tradition is that it originated in the missions of two Apostles of Jesus Bartholomew and Thaddeus, in the 1st century. The church would therefore be one of the oldest denominations of Christianity.