Ashot's prestige rose as he was courted by both Byzantine and Arab leaders eager to maintain a buffer state near their frontiers. The Caliphate recognized Ashot as "prince of princes" in 862 and, later on, king in 884 or 885. The establishment of the Bagratuni kingdom later led to the founding of several other Armenian principalities and kingdoms: Taron, Vaspurakan, Kars, Khachen and Syunik. Unity among all these states was sometimes difficult to maintain while the Byzantines and Arabs lost no time in exploiting the kingdom's situation to their own gains. Under the reign of Ashot III, Ani became the kingdom's capital and grew into a thriving economic and cultural center.
The first half of the 11th century saw the decline and eventual collapse of the kingdom. With emperor Basil II's string of victories in annexing parts of southwestern Armenia, King Hovhannes-Smbat felt forced to cede his lands and in 1022 promised to "will" his kingdom to the Byzantines following his death. However, after Hovhannes-Smbat's death in 1041, his successor, Gagik II, refused to hand over Ani and continued resistance until 1045, when his kingdom, plagued with internal and external threats, was finally taken by Byzantine forces.
The weakening of the Sassanian Empire during the 7th century led to the rise of another regional power, the Muslim Arabs. The Umayyad Arabs had conquered vast swaths of territory in the Middle East and, turning north, began to periodically launch raids into Armenia territory in 640. Theodore Rshtuni, the Armenian Curopalates, signed a peace treaty with the Caliphate although the continuing war with the Arabs and Byzantines soon lead to further destruction throughout Armenia. In 661, Armenian leaders agreed to submit under Muslim rule while the latter conceded to recognize Grigor Mamikonian from the powerful Mamikonian nakharar family as ishkhan (or prince) of Armenia. Known as "al-Arminiya" with its capital at Dvin, the province was headed by an ostikan, or governor.
However, Umayyad rule in Armenia grew in cruelty in the early 8th century. Revolts against the Arabs spread throughout Armenia until 705, when under the pretext of meeting for negotiations, the Arab ostikan of Nakhichevan massacred almost all of the Armenian nobility. The Arabs attempted to conciliate with the Armenians but the levying of higher taxes, impoverishment of the country due to a lack of regional trade, and the Umayyads' preference of the Bagratuni family over the Mamikonians (other notable families included the Artsruni, Kamsarakan, and Rshtuni) made this difficult to accomplish. Taking advantage of the overthrow of the Umayyads by the 'Abbasids, a second rebellion was conceived although it too was met with failure partly because of the frictional relationship between the Bagratuni and Mamikonian families. The rebellion's failure also resulted in the near disintegration of the Mamikonian house which lost most of the land it controlled (members of the Artstruni house were able to escape and settle in Vaspurakan).
A third and final rebellion, stemming from similar grievances as the second, was launched in 774 under the leadership of Mushegh Mamikonian and with the support of other nakharars. The Abbasid Arabs, however, marched into Armenia with an army of 30,000 men and decisively crushed the rebellion and its instigators at the battle of Bagrevand on April 24, 775, leaving a void for the sole largely intact family, the Bagratunis, to fill.