According to legend, Dadi was one of seventy disciples who studied under St. Thaddeus, the apostle of Jesus Christ who evangelized Armenia along with his fellow apostle St.Bartholomew.
When Dadi was murdered in the Armenian province of Upper Khachen in Artsakh, a monastery was erected in his honor on the left hank of the River Tartar-the site of Dadi's martyrdom-in the 1st century.
After more than a thousand years of vibrant operation, Dadivank's spiritual life was violently disrupted by the invading Seljuks; but in the 13th century, the monastery was revitalized by Arzakhatun, a noblewoman of the Vakhtangian princely dynasty.
Arzakhatun's husband and two sons, Hasan and Gregory, had been killed in the defense of Armenia, and her benefactions to Dadivank were made to honor their memory. The great lady exhausted her labors, her wealth, and her remaining days in the accomplishment of that mission.