The Armenian Rite is a liturgical rite used by both the Armenian Apostolic and the Armenian Catholic churches. Isaac of Armenia, the Catholicos of All Armenians, initiated a series of reforms with help from Mesrop Mashtots in the 5th century that distinguished Armenia from its Greek and Syriac counterparts. These reforms included a retranslation of the Bible and a revised liturgy. During the Crusades and afterwards, missionary activity by the Latin Church influenced liturgical norms and induced some Armenians to join the Catholic Church. The modern Armenian Rite features elements and interpolations from the Byzantine Rite and Latin liturgical rites, with the celebration of the Eucharist emulating the Liturgy of Saint Basil.

The Armenian Apostolic Church is the national church of Armenia. Part of Oriental Orthodoxy, it is one of the most ancient Christian institutions. The Kingdom of Armenia was the first state to adopt Christianity as its official religion under the rule of King Tiridates III, of the Arsacid dynasty in the early 4th century. According to tradition, the church originated in the missions of Apostles Bartholomew and Thaddeus of Edessa in the 1st century. St. Gregory the Illuminator was the first official primate of the church. It is sometimes referred to as the Armenian Apostolic Orthodox Church, Armenian Church or Armenian Gregorian Church.