Armenia lay to the north of Azarbaijan and Jazira. It was bounded in the east by the Caspian Sea, and in the west by the Black Sea.
After the conquest of Azarbaijan, Umar gave the call for a march to Armenia. From Azarbaijan, Bukair bin Abdullah moved at the head of a Muslim column along the west coast of the Caspian Sea.
Crossing the border the Muslim forces reached Bab. It was ruled by Shahrbaz, a Magian. The majority of the people were Armenians but Shahrbaz was a Persian and he owed allegiance to Persia. Having come to know of the conquests of the Muslims Shahrbaz was not in a mood to resist the Muslims. He waited on the Muslim commander Bukair and told him that he had little sympathy for the Armenians. He was a Persian and owed allegiance to Persia, but as Persia itself had submitted to the Muslims he was prepared to do the likewise and submit to Muslim rule. He was offered the usual alternative. He said that he had warlike people with him who would be an asset to the Muslims in their wars against other people. He pleaded that as they would be prepared to fight along with the Muslims, they should not be subjected the stigma of Jizya. The matter was referred to Umar, and he agreed to the suggestion subject to the provisos that if in any year there was no war they would pay Jizya and also that those who did not participate in the war would pay Jizya. This was agreed to by Shahrbaz, and the peace treaty was drawn up accordingly.
Thereafter the Muslims continued their triumphant march forward. A column under Bukair conquered Qan, an important frontier town. A column under Habib b. Maslamah marched on Tiflis. A column under Hudheifa marched to the Al-Lan mountains. Another column under Abdul Rahman bin Rabih reduced Baida.
This multi-pronged advance into Armenia came to a halt with the assassination of Umar towards the fall of the year 644 A.D.