He was the younger son and successor of Gregory the Illuminator, the founder and first head of the Armenian Church and his wife, Julitta (or Mariam) of Armenia.
Aristaces was born in Caesarea of Cappadocia to Gregory the Illuminator and his wife Julitta (or Mariam) of Armenia.
When Aristaces grew up, he went under the tutelage of a monk called Nicomachus, who sent him to live as an ascetic in the desert.
[3] Aristaces is also said to have participated in an embassy together with Gregory and King Tiridates to the newly converted Roman emperor Constantine the Great, although this is considered "purely legendary" by scholar Robert W.
Faustus of Byzantium writes that Aristaces died "a confessor's death" but gives no further details, while Movses Khorenatsi claims that he was murdered in Sophene by a governor named Archilaeus in retaliation for being reprimanded by the Catholicos.