In Persia he had been known as a defender of the faith of the Armenian Apostolic Church against the activities of the Catholic missionaries and in 1682 had published his book defending the traditional faiths of the church under the title Girk' atenakan, vor asi Vichabanakan.
When Catholicos Nahabed died in 1705, there was still much confusion and turmoil amongst the people and so the pontificate stayed vacant for more than a year until Alexander of Julfa was called to the throne by general consent in 1706.
Although initially Alexander I sent a letter of allegiance to ruling Pope Clement XI in 1707 at the beginning of his reign,[1] Catholicos Alexander II soon afterwards became in conflict with the Roman Catholic Church greatly concerned and exasperated with the excessive activism of the Catholic missionaries.
[2] As a result of his efforts, two decrees were issued by then incumbent Safavid king (shah) Sultan Husayn (r. 1694–1722) that restricted the rights of the Catholic missionaries' rights with respect to the Armenian population living within the Safavid Empire.
[3] Alexander I died in Etchmiadzin on 22 November 1714 and was buried west of the main cathedral.