Catholicosate of Aghtamar (Armenian: Աղթամարի կաթողիկոսութիւն, Aġt’amari kat’oġikosut’iun) was an independent see of the Armenian Apostolic Church that existed for almost eight centuries, from 1113 to 1895 and was based in the Cathedral of the Holy Cross on the Aghtamar Island (Turkish: Akdamar) near Van, in present-day Turkey.
The catholicosate was established by Archbishop Davit, who was related to the Artsrunis, the ruling dynasty of the independent Armenian Kingdom of Vaspurakan.
By the late 19th century, the Catholicosate of Aghtamar ruled over the southern shores of Lake Van: Shatakh, Khizan, etc.
The catholicosate was largely discredited and dissolved in 1895, amid the Hamidian massacres due to disputes with Etchmiadzin and corruption.
[2] The catholicosate remained vacant until the Armenian genocide and was formally abolished by the Turkish government in 1916.