The reign of Adarnase IV was marked by a change in Georgia's political orientation, as it left the Byzantine sphere of influence to join Armenia and, by extension, a declining Abbasid caliphate.
He took advantage of Byzantium's campaigns towards Italy to assert his independence, allying himself with Ashot I of Armenia and the Abbasid Caliphate in a risky diplomatic strategy.
[5] In 881,[6] at the instigation of Byzantium and the powerful nobleman Liparit Baghvashi,[7] a conflict broke out between David I and Nasra of Tao-Klarjeti, a young cadet of the Bagrationi dynasty.
Byzantium refused to recognise him as the eldest of the Bagrations and gave the title of Kouropalates to his cousin Gurgen, continuing the Roman policy of dividing the balance of power in Caucasus, but the official reason being the young age of the new duke.
[8] After ravaging many Georgian provinces without much opposition, Nasra, reinforced by local nobles[11] and the Alanian ruler Baqarat,[12] attacked Samtskhe and Tao.
[9] Adarnase led a resistance and was supported by Ashot of Armenia, Kouropalates Gurgen[8] and Liparit Baghvashi but his troops were considerably outnumbered by the pro-Byzantine forces.
[8] The victory in 888 put an end to the Byzantine invasion of South Caucasus and secured the independence of Armenia and Georgian lands, while solidifying the domination of the Bagrationi dynasty branch of Lower Tao over Iberia.
[15] The historian Valeri Silogava has surmised that Adarnase's crowning as king might have occurred, in a symbolic move, at the ancient Iberian capital of Mtskheta, as suggested by an asomtavruli inscription—probably a 17th-century reinstatement of an earlier epigraph—at the Samtavro Monastery.
[16] The geopolitical importance of Adarnase's action has also been noted by modern historiography: by taking the title of king, he proclaimed his independence from the autocratic power of Byzantium, which did not allow any monarch within the empire other than the emperor.
[17] While the independence of the Kingdom of the Iberians was recognised by its neighbours, the status of relations between Adarnase and Armenia was unclear: according to the historian Hovhannes Draskhanakerttsi, Adarnase's policy merely followed that of Ashot of Armenia, marking a vassalage of the new king towards his Armenian neighbour, but Roin Metreveli assumed that relations were based on bilateral recognition and the Georgian king used Arab-Armenian diplomacy to declare his independence.
[13] Adarnase IV began a policy of expansion towards the south, fortifying the city of Shavsheti and attaching numerous Byzantine provinces to his kingdom, as far as Erzurum.
[23] When the emir died of illness in 901 and was succeeded by Devdad Ibn Muhamma, who made peace with the Christians, Adarnase took part in a celebratory banquet with his Armenian counterpart at Yerazgavors.
Prince Padla I of Kakheti and his successor Kvirike I became increasingly powerful in eastern Georgia and pursued a policy of friendship with the Emirate of Tbilisi and Sajids, while the nobles of Kartli took advantage of Adarnase's attention to the south to obtain a large measure of autonomy, which meant that the Iberian kingdom lost de facto control of the region.
[12] Around 900, Adarnase IV, seeing Armenia's inability to cope properly with the Arab invaders and to balance the growing powers of Kakheti and Abkhazia, himself began to have ambitions for total domination of South Caucasus.
[24] Smbat's influence over the kingdom of Adarnase IV put it on a direct collision course with Abkhazia, whose king Constantine III remained a loyal ally of Byzantium.
[12] Adarnase and Smbat formed a united opposition front[18] to defend Gugark, an Armenian-Georgian province to the south of Kartli,[17] where the Iberian king camped with his Armenian counterpart.
[18] In 905, Adarnase IV began to develop a plan to invade Armenia, kill King Smbat and remove his line from the throne in order to annex his kingdom.
[29] In 905,[30] Yusuf ibn Abi'l-Saj, the Sajid emir of Azerbaijan, revolted against his Abbasid overlord and Smbat was instructed by the Caliph Al-Muktafi to put an end to the rebellion.
[33] When Smbat asked Adarnase for help, the latter refused and allied himself with Sajid,[15] who expelled the Abkhazians from Kartli (returning the province to Adarnasse's control[34]).
[28] In 909,[28] Yusuf returned to devastate South Caucasus and attacked Samtskhe and Javakheti,[31] two provinces officially part of the Kingdom of the Iberians but under the direction of the powerful Duke Ashot the Immature.
[35] In 912, he laid siege to Qeuli, which was defended by the Armenian army[36] and, due to a lack of Georgian defence, a militia led by a young Gobron: the latter was eventually captured and martyred by the Sajids along with 133 of his troops, while Adarnase tried to ransom them to freedom.