Avarayr battle is one of the largest battles in the history of Armenia, took place on the Avarair field between Armenians led by commander Vardan Mamikonyan, who rebelled against the forceful planting of the earth. Sasanian army was three times greater than the strength of the Armenians. During the battle, both sides suffered heavy losses, and Vardan Mamikonyan himself was killed.
The lack of outside help from the rebels and the transfer to the Sassanid side of part of the Armenian nobility led by marzpan Vasak Suny predetermined the victory of the Persians. Despite the desperate courage of the rebels, they were defeated by superior forces of the enemy and, having broken up into small groups, were forced to seek refuge in remote mountainous areas. Sasanian troops gradually crushed the scattered pockets of resistance, some of the captured leaders of the uprising were executed. However, frightened by the enormous size of the uprising, the Sassanian ruler Yazdegerd II was forced to abandon the violent conversion of Armenians to Zoroastrianism, restored self-government, returned the privileges of local nobility and the Christian clergy.
Sources:
Ter-Sarkisyants A.E. ; Institute of Ethnology and Anthropology
The history and culture of the Armenian people from ancient times to the beginning of the 19th century
The RG Hovannisian of The Armenian the People from Ancient to Modern Times