Isaac of Armenia

Saint Isaac of Armenia
Portrait by Stepanos Nersissian
Catholicos of All Armenians
Born	c. 354
Died	c. 439–441
Venerated in	Oriental Orthodoxy Eastern Orthodoxy Roman Catholicism
Feast	9 September (Roman Catholic Church) [1] Saturday preceding the penultimate Sunday before Lent (Armenian Apostolic Church) 20 November

Isaac or Sahak of Armenia (354–439) was Catholicos (or Patriarch) of the Armenian Apostolic Church. He is sometimes known as "Isaac the Great," and as "Sahak the Parthian" (Armenian: Սահակ Պարթեւ, Sahak Parthew", Parthian: Sahak-i Parthaw) owing to his father's Parthian origin, while his mother was an Armenian princess of the Mamikonian family.