The name is derived from the historic Aragatsotn canton of Ayrarat province of Kingdom of Armenia.

The diocesan headquarters are located in the provincial capital Ashtarak, while the cathedral of the diocese is the Saint Mesrop Mashtots Church in the nearby village of Oshakan.

After the independence from the Soviet Union, Armenia has been divided into provinces based on the territorial administration reform of 1995.

During the following year, the Diocese of Aragatsotn was officially founded upon a kontakion issued by Catholicos Karekin I on May 30, 1996.

Here is the list of churches, monasteries and chapels functioning under the jurisdiction of the Diocese of Aragatsotn, along with their location and year of consecration: This is an incomplete list of inactive or ruined churches and monasteries in the territory regulated by the Diocese of Aragatsotn: