Battle of Avarayr between Armenian rebels and the Sasanian Empire takes place. The Sasanids defeat the Armenians militarily but guaranty them freedom to openly practice Christianity.
The Battle of Avarayr (Armenian: Ավարայրի ճակատամարտ Avarayri čakatamart) was fought on 2 June 451 on the Avarayr Plain in Vaspurakan between a Christian Armenian army under Vardan Mamikonian and Sassanid Persia. It is considered one of the first battles in defense of the Christian faith. Although the Persians were victorious on the battlefield, it was a pyrrhic victory as Avarayr paved the way to the Nvarsak Treaty of 484 AD, which affirmed Armenia's right to practise Christianity freely.The battle is seen as one of the most significant events in Armenian history. The commander of the Armenian forces, Vardan Mamikonian, is considered a national hero and has been canonized by the Armenian Apostolic Church.