Armenia was the first country in the world to adopt Christianity as a state religion in 301 a.d. Christianity was introduced into Armenia much earlier, during the first century (60-68 a.d.) by two of Christ's disciples Bartholomew and Thaddeus. They came to Armenia from Asorestan and Capadocia. They baptized stately families and common people and are known as the first "Illuminators of the Armenian World".

During the first two centuries, Christians in Armenia were forced to practice their religion secretly amongst a majority of Zoroastrians. This situation lasted until 301 a.d. when Christianity gained support from the state.

Christianity was adopted in Armenia during the reign of King Trdat the 3rd and under the patriarchal leadership of Grigor the Illuminator, who baptized the king and the royal family in the Arax River, the Armenian Apostolic Church was established, with Grigor the Illuminator as its first Armenian Catholicos.

The Armenian Apostolic Church is the national church of Armenians. Its spiritual and clerical center is the Mother See of Holy Echmiadzin. The Armenian Apostolic Church is a religious unity with the Supreme Patriarch and Catholicos of All Armenians at its head. At present the Catholicos of All Armenians is His Holiness Garegin the 2nd.

Armenia is an open-air museum of Christianity. There are thousands of Christian monuments such as monasteries, churches, chapels and cross-stones, manuscripts, icons, etc. The Armenian churches and monasteries are built throughout Armenia and can be found in secluded gorges, on the peaks of towering mountains, hidden in forests and nestled in valleys. More than spiritual centers, these churches have also served as medieval educational and research institutions. Each reveals impressive and unique architectural features, and is accompanied by its own enlightening stories and secretive spirit. Many of these monuments host thousands of pilgrims every year.

The first book written in the Armenian alphabet was the Holy Bible, translated in Armenian as "The Breath of God." The Holy Bible and Gospels have been copied numerous times by Armenian monks and as a result nearly 20% of over 14,000 Armenian manuscripts preserved in the Matenadaran, Yerevan's museum of ancient manuscripts, are Gospels or Bibles. Nearly all illuminated Armenian manuscripts up to the twelfth century were Gospels.

Christianity, and the Christian mindset of being loving and kind, plays a major role in the Armenian daily life of this nation, which celebrated the 1700th anniversary of Christianity in Armenia in 2001. Together with preserving the Christian ancient traditions, the Armenians treat as a commandment the first sentence written in the Armenian alphabet, set down by the creator of the Armenian alphabet, Mesrop Mashtots: "Know wisdom and instruction; perceive the words of understanding" as a commandment and strive for enlightenment and the more progressive.